Crypto exchanges seem likely to persist in some form for the foreseeable future. After all, it only takes 1, as "mtgox" was showing many years ago, and Binance shows today, in the sense that it dominates.
And if we look sideways to other 'nefarious online activities' - even after literally decades of concerted efforts, jailings, etc etc, thepir^tebay dotorg is still perfectly present, exactly as pir^tebay-ish as it ever was, along with it's endless host of similars. The only way commercial business ameliorated their effect was, ultimately, to adopt the tech and approach, and be better at it - in the process, displacing the nefarious.
That'll be a market contraction of 1000x. The uses of crypto will then be extremely limited.
I think it's safe to say that exchanges are crypto for most people.