Whatever "freedom" or "options" could possibly mean in this context, adding more restrictions compared with previous games (at least in "personal" department) makes sense.
The first one had amnesiac without roots, additionally affected by whatever "emotional atrophy", even if it was less significant or less "chemical" than in average case. Add to that he just lost decades of experiences, character development, relations etc. Player has - and I guess *should* have - a lot of control over what happens in his private life. Then stuff happens, some memories come back, soon Geralt lives his life for a while without players' interference, until he wakes up in that tent. I still don't get the rage behind that tbh, it's like people expected their "shanified" decisions were suddenly supposed to result in what, "until death" relationship because reasons? If there was a big dowry involved, with Geralt being a nobleman - or a peasant - then sure... Thankfully, he is not MMO character either. (which makes me wonder if Witcher I wasn't a better choice for open world game instead of 3, but hey...)
Second game? With more memories coming back, Geralt didn't even get a choice that could be comparable with the previous game, it was more like deciding for or against Triss, Ves is nowhere near that dilemma, a side story, both literally and figuratively and with obvious disparity, that is not even concluded (mostly because there was nothing more to conclude). Whatever people would like to see, Geralt offers no indications it was anything more for him.
Then we get to the third game, with Geralt being his own man again, with all those years and experiences back in his head. Sure, whatever is shown by the story can make him reevaluate and perhaps make other options available. Make it convincing enough and hell, let him marry a mermaid for all I care - but horse before the cart, with plausible story offering an explanation, not because he meets a mermaid with funny dialogue lines and some players feel "their" Geralt "connects" with her based on sketchy interpretations or, heck, just on "because I want it so". That last argument should make the least sense now, with hero being the opposite of a blank slate. It doesn't mean we have to suddenly play a monogamous witcher, this guy didn't exactly spurn Fringilla in the middle of a similar journey. But there's a big difference between some opportunistic one-night-stands and "seducing" or whatever you call actively pursuing a woman over time you don't really have. Makes no sense. What else, 0-100 Seduction Progress Bar?
(not-so-related thing after reading some posts in this thread)
As for sex without any significant strings attached (either by a story or by players)... We get constant reminders in books that witchers were... going around, at least in the eyes of "normal" people. Granted, if it's mentioned right next to being an abomination, magical, unnatural freak offending the gods, certain hyperbole is a given. But on the other hand, there's no smoke without fire - and it's not hard to imagine they might be both compensating for screwed up emotional side and also lacking empathy, which in turn results in treating sex as instrumentally as possible. Add in all factors that were already mentioned time and time again like sterility, immunity, that magical-ish aura of sorts, word of mouth about their "experience" or even freak factor. Last, but not least, women themselves who might actually have different notions about sex than they do in whatever cultural circle gamer is from; oh and there's no christian morality to dictate anything about sexuality either, aside from some random weirdo monks here and there. That would be more than enough to justify even the silliest Witcher I pieces, with some of them transferring to Witcher 3 assuming no clashes with more important things that part introduces. But here's more...
With only a shell of Geralt being playable in Witcher I, even cards have their place - all those "it's objectifying" arguments do not specify why he shouldn't be able to act exactly like that, especially with what's been mentioned above. He is not a role model, this is not a educational game either - and players have quite a lot of ways to choose a different behavior. As for women being portrayed as if their sexuality is the only bargaining chip - well, it very often was. Gold? Not really. Influence? Sometimes, if story supports it - how often influence over a dumb village elder means anything, really. Information? Sure, Geralt totally needs to know butcher's son has herpes. Thing is, the lower you go on feudal ladder, the bigger the chance NPCs, where "N" stands for "nobody", can offer you *literally* nothing except for a few coins, usually pooled by the entire village or a district. If we get a story that suddenly has each of those penniless NPCs being able to offer you a secret entrance to the castle, rare meteorite steel found in a latrine, family heirloom ring that makes you invisible and brings some random screaming wraiths... then it's contrived and it basically screams "I am here for the sake of appearances". Meh.