Max in BTC vs. Binance CMC top 10 cryptocurrency equal weighted index

As the title says, I’m trying to decide between these two to invest long term. On one side I want to have diversified portfolio, on the other side I’m thinking if BTC goes down all the others go the same way and so on. For now I’ve been DCA investing in the index for a year now. But now I’ve started to question whether if it’s worth it (even if it is on the green side). I would like to hear some opinions about these two choices.