money because their limited supply
makes them deflationary.”
It's like saying: cars are not good for transportation because their combustion engine is polluting.
Not all crypto are deflationary. First one that has no limited supply that came into my mind is Dogecoin.
Then, crypto or money are just means of transferring the value (labor hours, products, services, ...). I don't think that limited supply is such a barrier, if the limit is high enough.
People tend to believe Bitcoin is in trouble because 21M is not a huge number. But they forget that it's 2100000000000000 satoshi. Big enough now?