I think the rationale is that knots may have an unknown bug that the network interprets as a hardfork. But I have no clue if that’s actually possible from a technical standpoint.
As far as I understand Knots has hundreds of unreviewed commits and thus is a much higher risk for unknown bugs.
As far as I understand it, if Knots had a consensus bug and the trigger condition were already present on-chain, we’d notice now. But if the trigger hasn’t occurred yet, the bug could sit quietly until some future block exposes it.
If a latent bug in Knots were never triggered until some future condition, then the visible split could appear only when Bitcoin Core itself changes the rules in a way that activates that edge case.
From Knots' perspective, in that scenario, Core would be at fault for creating the split.
From Core's perspective, Knots would be at fault for being divergent.
