Everything goes up and down. There is not a single asset that grows 0.1% per day and never go back. There is only one reason why BTC dumped - its becuase it pumped hard before. You dont want BTC to dump? You need to stop it from pumping - taking it out from all exchanges and blocking P2P trading - impossible.
"bitcoin plummets"
now - BTC @35k
01.2021 - BTC @20k
01.2020 - BTC @10k
01.2019 - BTC @4k
"fall of bitcoin"
Sarcastic post but reasonable to accept

People keep calling this is a bear market but they don't even review what is the value last year and what is it now.
It's the same mechanisms that controll all financial markets. Unfortunately I don't think there is much we can do about it.
if we will act together ? of course we can do big for this .. Not participating in any dumping while manipulation is at place will surely make them fail in their targets.