Having hobbies isn’t a waste, provided it’s not hurting you/others in the broader context of your life. Collecting isn’t a hobby I can relate to, but if it’s not getting in the way of other financial goals/obligations, it’s probably at an ok level.

All I’ll say is don’t be hurt if no one wants to take a massive collection of books down the line, even if they enjoy reading.

A large physical collection of anything can become like an albatross for those who inherent it. Not saying that will happen, just that it can.