It's been a while since I saw the first Borat and I haven't seen the second one, but iirc most of it just treated Kazakhstan as a generic "third-world" country rather than making any points about Kazakhstan specifically. There was definitely an attempt to satirise Western views about the Global South, but I'm not convinced it was a particularly successful attempt, especially since the film kind of meandered too much to really have any clear messages (which I suppose is inevitable when you're filming so much unscripted stuff).

I guess another issue is that it's probably somewhat annoying for Kazakhs that one of the very few times there was any attempt to depict their culture in Western media, it was a ridiculous caricature. I don't think it would have hurt to have just made up a country instead.

However, I don't think comparisons to blackface are ever really very helpful. Blackface has a pretty unique history, and the arguments people make against blackface don't look anything like the arguments they make against Borat, which kind of suggests they aren't similar situations. And let's not legitimise the "iF yOu RePlAcE tHe WoRd BlAcK wItH tHe WoRd CoNsErVaTiVe" garbage.

Fwiw, as a gay guy I really disliked Bruno. A lot of it wasn't even particularly over-the-top or absurdist, it was just portraying exactly what huge numbers of straight people think about us. I mean, when there is so much political discourse over whether it's acceptable for LGBT people to be parents, the idea of a straight guy going round pretending to be a gay dad who neglects his kid, treats it like a status symbol and puts it into sexual situations is just... well, I don't really get where the humour is supposed to be. The whole reason why there is a controversy about same-sex parenting is because loads of people expect that it results in precisely those things.