I don't understand this statement. What stops me from mining my own transaction is the infeasibility, considering variance, of mining a block with whatever tiny amount of hashpower I can muster.
With a very decentralized alternative to current pools (that addresses variance somehow), I see certainly a change to that situation, although it'd be kind of complex and not just "I mine my own txs if I want".
The social network of the future: No ads, no corporate surveillance, ethical design, and decentralization! Own your data with Mastodon!