At the moment, the answer to that question is NOTHING. When the market is getting down, we should have sold everything and join the retreat movement. This is one of the many things I have with cryptocurrency market...while we are rejoicing when its volatility is positively hitting the chart we feel disillusioned when the other side of the coin is the one reigning in. I feel like trapped as I failed to make my move when Bitcoin was almost at the $100K zone...now it is dancing in the vicinity of $80K which proved the prophecy of CZ in an X post correct...alas I did not listen to him and the many red signs.
I don't think the answer should be nothing, rather the answer should be "Hold', In economic perspective, when the market is going down the solutions is not to sell, but to Hold on to your position untill a rebound or recovery is archived.
Now, if everybody decides to sell his coin/tokens, be it altcoins because the market is going down, wouldn't it crash the entire market, even Bitcoin to the zero price level? Consider the investors that has been holdings altcoins since 2018, if they all had sold their tokens simplely because the market is going down, then by this time, all altcoins should have gone to tin air.
As a matter of facts, the best answer, in my opinion as an Economicst is hold, hold until full market recovery. Panic selling, sentiments, emotions shouldn't be a threat to a good investors, but patience and to sustain the market prices, investors should be able to HOLD their positions.