Also there is no HFT in cryptos: there is no colocation and not a single exchange can support either the market data dissemination or order processing capabilities right now. Every crypto exchange is horribly slow and appears to be terribly written.
The ones that could be run are often the same that were run on the exchange floor but you wouldn't call those 20 years ago HFT.
HFT'ers collocate because it gives them an edge, they were HFT'ers before they discovered that edge, collocating isn't what makes it HFT. Trying to trade faster than your competitor, competing on speed, that's what makes something HFT.