If defaults don't matter, why did Core devs spend political capital changing them from 83 bytes to 100KB? Technically you can set `-datacarriersize=83` in your config. Practically, 99% of nodes run defaults - which means the 100KB policy is consensus for mempool acceptance. "Anyone can revert it" ...

Core has scheduled this manual config item for future version deprecation (removal). Thus, eventually enforcing no OP_Return limits.