The topic was created long ago but I still want to give my advice. If anyone invests in Bitcoin, I think, it is always a good time to invest. Yeah at the bear market we can buy it cheaper even below 30K, who knows. But in the long run, I mean 4years to 10 years, it will make too many new millionaires.
For other coins or tokens, we should try to buy at the bottom of the bear market. And should only buy well-known projects. Buying altcoins now for long term is not a good idea.