^This. I weight my allocations based off market cap so 91% of my investments would go into index funds and no more than 9% overall goes into Cryptocurrency -- 6.5% of which goes into Bitcoin and 2.5% might go into non-Bitcoin cryptos.

I think the whole crypto market is pretty speculative. Either the ultimate Bitcoin replacement will be a nice fork or airdrop off of Bitcoin or the ultimate Bitcoin replacement will be something completely separate and will gradually render Bitcoin worthless.

Cash is also a pretty underrated asset class too.