They can start anytime i guess. There are a lot of mega holders who I guess do spend them. The problem is till it has not reached some sort of peak and plateaued out, the cost in spending it right now is too much. That is what bitcoin has taught HODLers time and time again.
Those who adopted early and got 100s of them free can talk about it being a currency and some sort of harbinger of revolutions but what about the people who got in at say 2000$, 3000$ and even now getting in at ~8000$. These people are doing it in the hope that it'll hit 100,000$.
They will possibly never spend it for real-world products. For ETH and some other crypto, maybe yes, but highly unlikely to buy a coffee or pizza. (never pizza of course//

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