In my understanding it is only different techniques within the different religions/spiritual practice that are different. Like in How to get in to Heaven or how to realize Nirvana.
So why are people so protective of their belief? Saying "my belief is the right one"
But when looking at the spiritual aspects of all religions, they seek something similar.
Not all people are as tolerant as you
For a lot of people religion is also a lifepath or a way of living. For instance, JW have to do certain things and are also taught to look at other people differently, because their "purpose" is not only to be good religious people, but to also spread the message with the overall purpose of saving people.
Obviously if they didn't care to much about what other religions are out there and all of them are equally good then doing all this seems kind of pointless. Therefore their view
IS the correct one and its their mission to spread it and save other. Now JWs is not an aggressive religion where you have to take up arms and fight others, in fact its the exact opposite, they are not allowed to join the military or get involved in politics, not even voting as far as I know.
So a lot of the things they do and live by are obviously affected by their religion, just as many others are.
Ultimately if you ask a Christian, Muslim or Jew about God, then there is only one God. All others are false ones. In certain religious views within these, believing in false gods is a sin.
For instance in the bible we see this:
Exodus 22:20
20 - “Whoever sacrifices to any god, other than the LORD alone, shall be devoted to destruction.
So there is a clear picture being painted within a lot of these religions, that other believes ain't really tolerated, and depending on how each group of believers interpret or are told what the meaning is, this could make them behave certain ways towards others. As we know there are many countries where being an atheist is punishable by death. Likewise we see punishments for certain sensualities, also in some cases death. You have other countries, where women for instance have to wear certain clothes etc.
The chance is that not all people living under these different rules agree with them. Like there are probably some women in these countries that don't like the idea that they can't get an education or have to wear these clothes, yet they are forced to it. So even within the same religion, you will have certain rules that reflect the believe of it, which is forced unto some people.
So in the end, I guess it boils down to what is considered "right" and what is not considered "right", because clearly if all people shared your view, then no one should be afraid to go to the streets and yell that they are an atheist or a women refusing to wear the burka etc. without it having any consequences.