As of now I don't think if it is the best time to invest because the prices of cryptos are already high and you know it could suddenly down anytime. Maybe it's better to wait to go down the prices then that's the best time to invest..
The bullish trend will always become the best time to sell. There was no reason to call the bull trend as the best time to invest and people must have accumulated more coins when their coin were trading at the bottom price.