I always used the term "Herosexual". But Playersexual works too.
And I have no issues with it. As long as the rest of the writing is up to snuff.
If you have Herosexual companions, then yes, the player can romance whoever they want. Which is good. It's choice and freedom. It lets you hook up with whoever you like (or like for the character you're playing) without having to worry about playing something specific just to experience a romance.
On the other hand, if companion orientations were set, you'd be more limited. And if they were to do that, they would expected to have VASTLY better writing for each (which sadly BG3 doesn't have). Where every character is well designed, with a detailed history including past relationships that would be brought up to help give your romance with them (or lack of ability to do so) more depth and meaning.
It would be great to see more detailed writing with character relationships, that you can explore as you get closer to them. But most games just skimp out on that. Which is a shame.