@kate @ariadne generally yes, if you take a known blob that's already out there for years and known to fix particular issues, then I see no issues.
But some systems make it a habit of blindly fetching and applying each microcode blob that's made available. Such a habit where new blobs are regularly introduced into a system without going through any kind of scrutiny first is not something that should happen for granted I think.
I would feel more comfortable with some control over that.