As I said before, my great uncle was self-taught. As far as I know, he didn't have any tutors either. And I know he had little money. At that time (turn of the last century for him) it was quite common. It's really not that special. I fail to see any great significance in Baha'u'llah. Lots of people were learned, there were very few schools in those days.
I am sorry, but I have to point out your comparison is not a fair and accurate comparison, for the following reasons:
Firstly, your comparison is a one dimentional comparison, and what I mean by this is, suppose Newton who was a well-known scientists, had done self studies too, and your uncle has done self studies: can we conclude your dear uncle is equal to Newton, just because they both did self studies?
Secondly and Moreover, all people, more or less do self studies, but, if we are comparing, the important question is 'How much', a person did self study. So, the second point is, not to over-generalize if you are comparing.
Thirdly, it is the matter of 'What' material or subjects did a person used for self study. Again, I do not see any fair and accurate data in your comparison.
Fourth dimension of comparison, should be the question of 'how long' did a person did self study. Again, i do not see any accuracy in your comparison.
Fifth, is really the comparison of the 'Result' of self study, which means how did the self study a particular person did, effect the world. Again, I do not see any fair or accurate comparison based on available information.
In general, I would suggest, you try to provide a fair comparison based on the above five dimensions at least in you comparison, and you must for each one of them, provide your references from historical evidences, so, it can be said that you truly is doing a proper comparison, a fair investigation with a fairly accurate results, free from bias!