Should aggregators hard-block trades with 99%+ slippage?

The $50M whale loss has me thinking — the user clicked through multiple warnings about extreme price impact. CowSwap showed clear warnings. Aave flagged it.

Still happened.

Is "we warned you" enough for DeFi UX? Or should there be circuit breakers that physically prevent trades above certain slippage thresholds unless you jump through extra hoops?

Curious what people think. Where's the line between protecting users and being permissionless?