Taril, no, ARPG took time before becoming popular. Diablo was controversial within the RPG genre as it didn't feature any roleplay element except playing a class and choosing some skills. Dragon Commander's mechanics were never popular, you have almost no games like that. Anyway, your argument isn't good, ARPG sells more than TB games, people will most likely play a RDR2, TW3, TES... than a TB game. No, they have decided to follow the standardized route like Bethesda did many years ago, like CD Projekt is doing, Ubisoft... which leads to less creativity overall, and less risks taken.
I've never heard of sex being a taboo in video games, that's a first in 45 years of gaming I have... That some countries don't want it, yes, and it's pretty easy to filter it, but they included it because it sells. No wonder BG3 is one of the most sold TB game (if not the most), it includes something the market wants, sex, and kinks.
Other D&D games are relevant to make a comparison. That's the purpose of bringing them. Anyway, you bring another argument in favor of less creativity and more standardization based on what sells, which is the opposite route of creativity and taking risks.