a few days ago ethereum experienced a drastic decline. and it turns out it's currently under $ 200! My personal predictions are wrong, and may not be true. what's the next step?

I think vacationing is a good idea while enjoying a vacation !!
Many competitors of ETH are much better already now. ETH boasts experience in the market, reputation, and marketing. But those merits won't get it so far. ETH has to solve real problems otherwise, it only will get worse!