Nowadays, no one believes BTC will dramatically drop to below $20K in 2021. Everybody is crazy in bull market , but risks are building up.
When it hit $20k in 2017 no one thought it would retrace back in the $3k's and it did. If bitcoins price history has taught anything is that ANYTHING is possible, so going back to 20k would not be crazy at all at this point. Never say never (although I'm very bullish at this point with everyone else)