Vast majority of holders didn't buy during the very short period where bitcoin was 20K. The maximum stable price was 10K or so. Bitcoin spent virtually the entirety of 2021 above 30K.
In fact it was really easy to make a lot of money
2018/2019 BTC spent 7 months below 4k USD. That's enough time for someone to do a garage sale or whatever and buy BTC. In 2019 you had 3 months to sell above 10k, which would give would give you more than 200% profit compared to 2% inflation. If that's not a hedge then I don't know what is.
If you bought the pandemic dip in 2020, you'd make 100% in 2 months.
If you bought at the 2017 top and sold a few weeks ago you'd have +100%. The average return of a real estate investment is 5% a year so if you bought a house and rented it out you'd only have 20%, but with the worst trades you could get in the last 4 years (buying 2017 top and selling now in a downtrend) you'd still be up by 60%.