Although I don't know the fundamental reason why all the coins are fell in price but I see it as another opportunity to buy cheap. Ethereum fell from $450 to around $323 and bitcoin from $3000 to around $2311. I think I should advise you to buy now so you will not complain in future and call it another pump.
Probably not the best idea to buy everything in sight! lol.
I would advise working to understand where the market is right, and where the market is wrong, then finding opportunity
before the corrections.