What rate is he getting on his crypto? I get ~4% on my fiat.

Some cryptos are doing better than that, so it's certainly possible to beat, but I wouldn't chance the volatility. Unless it's doing better than that.. then I think inflation is eating the crypto, not the other way around?

Edit: I see, because Bitcoin isn't adding additional coins, it's "non-inflationary". I think this is moot when you ultimately have to transact through fiat, so the only thing that matters is BTC-USD conversion rate.