That's not a part about Agile, but about Scrum.
Also, the “dedicated” part isn't even essential to Scrum.
> We had agile coaches at my company recently and it was one of the more painful experiences of my career. They would try to add [...]
That's a different issue than a dedicated ScrumMaster role, and anti-Agile, as team ownership of process is central to Agile. Consultants external to the team (whether internal to the org or external there, too) trying to impose process is the antithesis of Agile. There might be a role for coaching in Agile, but it certainly isn't process advocacy.
They are now delving into solutions architects and seem to be expert software engineers who ask questions like, “but isn’t that simple? How come it’s going to take so long” etc.
Nightmare.
I find it telling that I never met scrum masters who can actually tell you what they’re working on or what their backlog is. Funny that?
You probably haven't yet experienced SAFE / Scaled Agile at a non-tech Fortune 500. There's worse things people can slap an Agile tag on :)