Theoretically, could widespread cryptocurrency implementation prevent DoS (Denial of Service) attacks in the future by requiring payment of a few satoshis per web server HTTP request
So for AJAX to get some piece of data, you're going to create a transaction, sign it with ECDSA, transmit it to nodes, shove it into mempools, and then make a miner mine it? Sounds like a DDoS against the Bitcoin network itself.
or would the process of screening out the unpaid HTTP requests slow things down as much as the DoS attack itself?
It would be much worse. You could prepay, however, but that still wouldn't solve things, since most DoSs are caused by sheer amounts of data, and not the HTTP requests themselves.
