if seen in 2018 there was a decline, but the decline occurred because indeed at that time Bitcoin was said to be a bubble, and that might be true, and now Bitcoin has recovered, if it returns to $ 10,000 then it is safe for us to trade
It was the year where long correction happened, and that is acceptable since bitcoin and altcoins went overprice in 2017 and in the first few months of 2018, and that is the reason why until now altcoin are still struggling because people are not investing anymore because they trust bitcoin now since it's stronger and able to slowly recover.