Yeah, the simplicity and also effectiveness of advertising algorithms are sometimes overstated.
There is a huge amount of data that is stored about users, and that does definitely make its way into the ads that we see. Grouping all the user information into ad categories is not a simple task, so there's a lot of mismatch that happens. But a lot of the time it's also location-based, time-based (when who views what) or even just what the biggest spenders want us to see based on our demographics. Tits and ass are fairly demographic agnostic, so they appear in a lot of feeds regardless of preference or orientation.
Right-wingers are fairly desperate to push their viewpoints and pay a lot to so, so we end up with a lot of vague associations or fully non existent ones resulting in that kind of content appearing in feeds. I'm a left leaning, queer and trans woman living outside the US and I see these bullshit ads from time to time (which for obvious reasons is pretty infuriating). I honestly think that having a small online footprint and using adblockers, privacy-friendly browsers and operating systems, etc. is going to become more and more common just as a mode of self-care.