Of course, and obviously, the best coin to hold is BTC.

And just to let you know, we can directly buy bitcoin without using grayscale though. As the saying goes, not your keys not your coin, so better first learn how to own your seed or private key and educate yourself how to protect and practice security hygiene.

Not going to bash any one those altcoins, but if you wanted to invest on them, then go for the prime mover as well, Ethereum.