How 'bout just spend the points. Stop saving them up like caps.
Hoarding SP is not a (real) problem here, lack of ingame information about limit is
The question is then I guess, would it be difficult to add a warning in game (like the "you are being followed" warning) say when the player hits 75 stored skill points or at 2 levels after an unselected perk.
The warning could just say something simple like "Don't forget to select perks and spend points or you will lose them".
It won't help a bot hah, but who cares about bots, this is about informing real players in the moment.