Yes, they are not living up to the requirements of the religion, as you have mentioned, and should carefully follow the catechisms and rulings if they wish to refine their religions or claim to be members of such.
As for Islam, the people who are actually practicing Muslims are likely much closer to following the requirements of their religion than are many of the people who call themselves Christians.
Furthermore, "Mutah" is not something most Muslims even believe in, it is not clearly mentioned anywhere in the Qur'an, and neither is the famous "polygamy" clearly prescribed.
This is what the Qur'an says:
Ayah an-Nisa` (Women) 4:3 Renditions at IslamAwakened.com
The multiple marriage thing has something to do with Orphans and their care and rights, and furthermore, it suggests "marry only one" to the orphan or whatever it is saying, or otherwise "marry only one wife" if you are concerned about unfairness, then also says:
4:129
"And it will not be within your power to treat your wives with equal fairness, however much you may desire it; and so, do not allow yourselves to incline towards one to the exclusion of the other, leaving her in a state, as it were, of having and not having a husband. But if you put things to rights and are conscious of Him - behold, God is indeed much-forgiving, a dispenser of grace.
So here is the issue:
Many cultures in the world had already been married to multiple women, and this was not abruptly outlawed. Most Muslims today are only ever married to one woman or one woman at a time.
Islam permits divorce, while Christianity according to the New Testament seems to suggest that divorce turns a woman into an adulteress, and this is not a "step forwards" but very harmful towards women potentially.
Other things which were not abruptly outlawed were Slavery, even though today most Muslims don't own slaves, in Christianity, slavery was not even suggested as something bad, and slaves being beaten up by their masters or treated cruelly even were told to return to their masters or owners, whereas the Qur'an in contrast counts the "freeing of a slave" as a good deed which the righteous are to perform and to expiate sins, a move in the right direction.
Sudden abolishment of Slavery would leave a complete population of dependents who had no support, money, care, nothing, as the Slaves were in many ways like children due to depending on the owner for food, clothing, care, and it was wrong and cruel to just say "go now, you're on your own", but they needed to be furnished with the ability to survive on their own and establish themselves as free people, otherwise they might be forced to survive through crime or become beggars.
The Qur'an did not move in the wrong direction in my opinion, it established a more sophisticated vision of God as well, one that is superior to anything which Christianity officially came to promote, such as the confusing terminology used in the Bible or Jesus the human man as God and the Son of God and God as a doting Father rather than a Non-Human superior being.
The Qur'an never said "go ahead, do mutah, divorce and separate a lot, deflower women" it has none of that, it has everything against that, in a much more decent fashion than Christian extremism saying that any woman who re-marries or is divorced by her Husband is an adultress.
The Bible also says many ridiculous and wrong things, by retaining the Jewish material in the Old Testament (which tells people that tribal interest taking is wrong but to go ahead and take interest from the surrounding people and nations) and then Jesus supposedly saying things like "gouge out your eye, cut off your foot and hand, drown people who hurt "these little ones" which people just take as a sort of joke to ignore, when Jesus questioned the Jews for their ignoring what he calls God's commandment supposedly which orders the Jews to "kill their children" if they show any form of disrespect to their parents, and then he gave this example when the Jews were trying to convince him to wash his filthy hands before eating food with them.
Jesus also says "I have come only for / to the Children of Israel" to the woman who was begging on behalf of her child and he was ignoring her and she was following him desperately, and had to call herself a dog for being a Canaanite or whatever because God is apparently a racist Man.
So no, nothing is going in the right direction there, and even though what you see on TV are tanned looking imbeciles yelling and juggling with grenades, that is not what is really in the Qur'an if one reads it carefully in its entirety, and in reading it carefully without the imbeciles in mind, one can see that the Qur'an is entirely superior to what is in the Bible on every single count practically as what is better and more helpful and more reasonable for human beings and just in comparison.
Where the Bible says women have to "cover their heads or else shave their hair off" and "are not permitted to speak in the Churches" or over a man, and that "Christ is to Man, as Man is over Woman" that a Husband is basically like a God to his wife? This is nothing like Islam or "headed in the right direction", and the Qur'an's words seem far more suitable and appropriate for the modern world than what was in the New Testament. You might think differently also if you were a women, forced by birth to feel a pressure to abide by such things when you are just a human beings (with boobs! BOOBS! YOU HAVE BOOBS! YOU CAN'T GET A DIVORCE AND IF YOU ARE DIVORCED YOU ARE AN ADULTRESS! BOOOOOBS!).
Yet, the Qur'an can be said to be the scripture of Moloch, Rimmon, and all the rest of "Allah's names". Do you believe that Asmodeus and Mammon are real entities? I'd like to know more about that, you could even make a different thread about Demonology since that is a favorite topic of mine and of great interest to me as to what people think on it all and each, their experiences, all that. I have a whole thread full of medieval demon names even.
The Muslims are the ones seen covering their heads, but nothing is no explicit or vigorous about this head covering business as apparently the writing in the New Testament for example.
You could also make a thread which lists all the commandments and acts and thoughts and whatever in detail that it takes to qualify as truly on the Straight and Narrow as a True Christian.
You're right that the Qur'an is a sort of "relaxation" from the eye gouging, hand and foot cutting, child abuser drowning, turn the other cheek, slay right in front of me all those who denied me as their King, a divorced woman is an adulteress, Christianity. The trouble might be that some of us might be calling the Devil, God:
Whose your Daddy? Dan?