Cryptocurrency projects uses .io or .info or .tech or .shit or whatever simple because .com is not available or it is more expensive.
Take for example.blockchain.info. they bought .com finally after 10 years, for millions
About that price, .IO is more expensive than .COM.
This information is wrong and makes absolutely no sense.
I reckon this, .io and other domains that are not .com are simply cheaper.
You can see on how much a sample .com is compare to a website that has .io through -->