In my opinion he didn’t intend it until charlotte rejected him, but i think that the point is that it doesn’t really matter what he intended with his actions. What matters is how his actions negatively affect those around him.

Functionally Penny was groomed by him and still suffers the effects of Bojack’s selfishness, immaturity and impulsive and inappropriate actions for years after the incident. Bojack is just as morally condemnable for what he did to Penny whether he intentionally groomed her or not.