Do you think that people squatting big weights with shoes, belts, and kneewraps are unable to manhandle heavy things?

You are absolutely not dependent upon them, they just make you more effective at doing this weird thing we've figured out where you put a loaded bar on your spine and sit down. This simulates no natural situation, but we've figured out that it has carryover to absolutely everything and trains us in an incredibly time efficient way. Crossfitters wear shoes with heels to squat and do oly lifts btw.