RPG numbers that increase in response to player activities are a direct incentive to engagement, especially in a game with a largely empty/copypasta world. with nothing better to do, players are going to want to interact with those RPG numbers simply because they are there.

if the last 25% skill isn't "really going to make that much difference" then might as well turn the current 75 into 100. otherwise devs should take responsibility for a half-baked system and make it more meaningful, rewarding, integrated, etc, or just scrap the skill system altogether.