The news is that Viltrox was told to stop. Probably Samyang too. That is it. So far.
The numerous "protest" videos uploaded on YouTube by various reviewers are sometimes accurate. Sometimes not.
Some repeat a rumor they read on Canon Rumors and then they irresponsibly extrapolate that rumor to include ALL 3rd party lens makers.
It may be Geopolitics/National Protectionist thing. Japan does not want China and South Korea to eat its (Canon's) lunch.
The Japanese manufacturers are cooperative among themselves.
So far have not heard Tamron and/or Sigma and/or Tokina being told to stop RF mount by Canon.
Even if that eventually materializes, it is a small deal. Just buy RF or RF-s glass. Was that very difficult?
There are many facets to this.
• For example, among Canon R camera owners, maybe 95% have no plans to buy 3rd party lens. Thus this becomes a non-issue.
• Most Leica SL2 (full frame) owners and S3 (medium format) owners probably have no intention to put a 3rd party lens on their camera body.
It becomes a shameful downgrade and embarrasses the owner.
Therefore Leica generally does not have this problem. Most of the owners self regulate by their own choice.