As far as EASA is concerned, the UK is solidly behind the IMC Rating - either retaining it just in the UK or grandfathering its privileges into something pan-European.
The problem is some other European countries, notably France and Germany. Over there, objections have come from airline pilots, their unions, and their national CAAs. However, none of these objections are based on any evidence whatsoever - they are merely adopting a "there must be no flight in IMC without an IR" position.
Obviously, to any thinking person, such opposition appears ridiculous as it is clearly based on blind prejudice and ignorance.
The task ahead is to come up with good safety data which can be used to convince these people, and IMHO this isn't going to be too hard because the evidence is clear: there have been thousands of IMCR holders flying on it for decades and there is very close to zero evidence of any of them having accidents attributable to the exercise of the privilege. On the scale of statistics, it doesn't get much better than this.
Which is not to say it will be easy because blind prejudice is hard to work with.