If you have a long term plan then stick to it. Most of those coins that went to an all time high back around New Year 2017/2018 they will never see those high prices again.
Other coin like Bitcoin will most likely see new all time highs in the years to come, going long on Bitcoin have since the beginning of Bitcoin been the best bet anyone cut make.
Most of my portfolio is just Bitcoins in a save wallet, and then I play around with 10-20% of my portfolio in Altcoins.