If the attribute says "encapsulate this", dropping just the attribute will create a blackhole as you will attract traffic that should be encapsulated and packets following this route will be dropped it if not.

I guess you're referring to RFC9012.

Yes, but then again since you have logs of why it was dropped (like I suggested in my first post, to log everything dropped), you can easily troubleshoot the problem. A much better outcome than flapping a BGP session for no good reason and creating route churn and network instability.

Or just drop the announced route (not the session) with the attribute you can't work with