This is all actually a little more complicated than at first glance, for a lot of reasons. I am confident in saying there is quite a lot of confirmationbias happening. Firstly the whole Fem Dom angle... it's a fetish and some people like it. Possibly you just have a lot of overlapping fetishes with things that tend to fo hand in hand? I haven't really seen a huge increase and a lot of the old classics around here have plenty of content that would classify, but have grown so large that the game isn't cantering on any specific fetish.
As for large breasts...
Firstly across the western world, bust size has been increasing for decades. We might assume average is b, but all the lingerie companies are saying it's d. No one else is keeping track statistically. Even then, as I write this, breasts the size you might find in one of my games are rare but that doesn't stop them from existing. Let's just say there is a pair within arms reach for me.
That allows me to write stories about large breasted people. More than just a marketing gimmick, the fact that they are real characters expressing real world problems. A lot of games are the same, because that's also what people want to read within the big booby community.
Which kind of brings me to my next point... are there actually that many large breast games?
I'm not going to lie and say they are a representative sample... but most games have one or two d cup characters for their large breast tag and some variety... and that's about it. Games that actually concentrate on the larger proportions are reasonably rare in my experience. In general you get better representation in porn than in comic books.
None of this means you should start liking these things in your porn, but I don't think they are as universal, or as insulting as you make out.