This really...I don’t think it will be busted- Ice types are terrible defensive, so this does not overpower them at all.
People make a huge deal about ice type defenses boost forgetting that ice types are still ice types with no resists other than itself and 5 weaknesses to common offensive types.
On top of basically any actually viable ice type being generally glass cannon too.
Like sure, certain pokemon may actually be able to live a extra hit, I get it, and may make some calcs skew a bit, like idk weavile actually living more than just wet noodle hits, but in the grand scheme it's still nowhere as good as some people make it to be.