The animation content itself is quite tame for an 18+ game, unless you lead a very sheltered life. It's not particularly different from, for example, the recent CD Projekt games, and really just follows the "romance" trajectory set by Bioware over the years; including that it is more amusing than arousing. I expect there will be mods on loverslab in time for those that want more explicit animations.
Where I found the game interactions lacking was ( as many have pointed out ) that most of the NPCs seemed to want to rip yours clothes off if you agreed with them once ( OK, exaggeration for effect ), which surprised me as the early access did not feel that way.
I appreciate that each NPC romance story is supposedly different, so I would expect the build-up dialog to feel more varied than it actually appeared in-game. There was some suggestion that the NPC "desperation" in the released game is a bug, which is possible. I will not replay the game until the frequent bug-fix releases settle down, maybe another 6 months, or after the formal mod tools are released.
I would also certainly agree with those that think act 3 was something of a damp squib. The early access hinted at a more complex political situation in the city than the released game provided. It may be that I simply missed a lot of act 3 content, but if so, it was not for lack of trying. Either I still have a lot to find, or the story was significantly simplified in an effort to actually ship it.
On the other hand, I don't think that the romance content was directly responsible for the lacklustre act 3, which was more of a design problem than a resource constraint. The romances are self-contained and orthogonal to the plot; you can ignore them and nothing really changes. If anything, the early access mania for Minthara and Halsin may have robbed us of one or more other NPCs, in particular a member of the small races that was datamined in early access.
All that is a long-winded way of saying, "no", I don't think the game is inherently over-sexualized, but it is buggy and has design issues that may make it feel that way to some players.
