It's always a good time to invest if we're planning it to hold for a long time. If we're aiming for a quick profit, the price right now is quite high, there must be some correction before the price going back to the top again. So it depends on the investment timeline that the investors decide at the start.
The price of cryptocurrencies at this time is not that high and is still half of the ATH price that all cryptocurrencies have achieved in the past few months, and if you want to make an investment, it is still very good now than having to wait for another correction which is still not sure to happen.