Why is my brother's BTC investment at a loss?

I've tried wrapping my head around this a few times. My brother keeps explaining why he's at a loss, but I can't stop thinking of 1 BTC as 1 BTC. He bought at the peak on Binance before the COVID crash and held. Over the past few weeks, I kept asking why he doesn’t sell, and his response was always, "I'm still not in profit." That confused me- he bought at $60K and added more at $50K. Then he pulled out a calculator and showed me how a 75% loss requires around a 300% gain just to break even. Does Bitcoin really work like this? I haven’t seen anyone else discuss this, so can someone confirm? I'm not into crypto, but I'm curious.