This is not true. Bitcoin Core does not try to “maximize the user experience of…transfers”. It has filtered transactions for various reasons, and maybe that previously, but that hasn’t been true in a long time.

Indeed, the system only works if miners are including transactions on the basis of fee alone; anything else is a slippery slope towards broad censorship. The fact that the protocol doesn’t enforce this is one of the biggest failings of bitcoin.

Ethereum is even working on fixing this, while we’re talking about whether it’s okay to live with it 😭.