It may be a perfectly routine occurrence offshore but only those airfields not in CAS onshore will have an unprotected instrument approach. It is an issue, especially when the airfield doesn't have radar.
The MAP for Gloucester takes you to the edge of the ATZ but then climbs you and turns you back to the NDB hold at 2800' - ie outside the ATZ in class G (normal hold is at 4000') . You are possibly IMC with no radar service where anyone can just fly through.
But people can and do fly IMC outside controlled airspace with no radar cover all the time. They don’t seem to crash very often. Well let me rephrase that, there is plenty of crashing due to pilot error but none due to mid air collisions in IMC. In aviation (and elsewhere of course) you have to analyse carefully what is actually dangerous and what isn’t. Sometimes stuff that looks dangerous actually isn’t, and stuff that looks safe is actually dangerous. Humans are bad at judging that sort of thing.
Anyway I would agree that having a serviceable radar would be a good thing. I don’t agree that having more controlled airspace would be a good or necessary thing.