It certainly works for some stations, but not for many other (from personal experience in France), and it would be trivial for radios to change their RDS / metadata system to circumvent ad blocking.
As long as it's only individuals doing this I don't see anybody reacting on a wide scale. Also there's no feedback of listener numbers depending on volume. So there's no way to detect people "adblocking" on radio, so there's no impact on revenue.
