Both can be true.

When you’re cultivating a relationship with a real person their wants and desires also factor into your choices, assuming you aren’t a psychopath. They will want different things from you, and keeping that to themselves and never pushing back just makes them miserable and builds resentment. Similarly, you don’t want to impose unreasonable expectations on them. Whether that’s related to their behaviour or their appearance, no one can reasonably expect to get exactly what they want 100% of the time, and that’s part of a healthy relationship.

…but if you’re constructing an artificial partner from a blank slate that’s completely bespoke to you, to choose anything other than an idealized match for all your desires is frankly insane, and to pretend otherwise is simply disingenuous.

I predict that once robotics and AI advanced beyond some particular threshold, human-on-human relationships will be seen as strange and needlessly fetishistic. Who would want some grimey partner with their own needs when you can generate an infinitely moldable soulmate?