They could also take the optional approach, just like with the turbulence update.
Realistic, Medium, Low / No icing.
Therefore this topic needs more recognition / votes.
But on the other hand, looking at Realistic Dangerous Weather - Physics Simulation with over 300 votes, there are certainly a few people interested in realism in that category.
They want realistic turbulence in storms / big clouds, but realistic icing is as much important and can bring some extra thrill into the simulation when picking the flight route and avoiding certain clouds and conditions because of real life consequences 