Pretty sure most people didn't buy BTC at $20K, which it never actually even reached. It didn't spend much time above $19K either.
If you look at the charts, it didn't even spend much time above $16K or so.
Most people lost huge sums of money because they invested in alts which are like 90% red. Look at Ripple or Dentacoin or what-not.
I assume most invested at like $12K and its half now, so its only a 50% loss. However the alts are a different story.
I think you underestimate the altcoins. This is a great speculative asset. Bitcoin will rise in price, I'm sure. But I am also sure that all who are now buying altcoins will earn more than those who buy bitcoin now. It is always necessary to maneuver skillfully and it will bring more income than holding.