Is it still verboten to acknowledge that RBF is normal behavior and disallowing it is the feature, and that feature is mostly there to appease some people's delusions that zeroconf is a thing? It seems a bit overdue to disrespect the RBF flag in the direction of always assuming it's on.
What flag?
The opt-in RBF flag in transactions.
There are two different common regimes which result in different incentivized behavior. One of them is that there's more than a block's backlog in the mempool in which case between two conflicting transactions the one with the higher fee rate should win. In the other case where there isn't a whole block's worth of transactions the one with higher total value should win.
These are not distinct scenarios. The rational choice is the highest fee block-valid subgraph of the set of unconfirmed transactions, in both cases (within the limits of what is computationally feasible of course).
It's weird because which of two or more conflicting transactions should win can oscillate back and forth depending on other stuff going on in the mempool. There's already a bit of that with child pays but this is stranger and has more oddball edge cases about which transactions to route.