They are just too useful of a defensive weapon.

I don’t mean they can’t be used a belligerent party, but their role is to defend an area and deny access, and they’re really good at it.

That’s not me justifying their continued use, just explaining why they’re still used.

If you’re a European country with a Russian border, you’re now certainly looking at using technologies perform similar role that are a treaty compliant, but much more expensive, or simply leaving the treaty.