All of this is based on my non-scientific sampling of sports analysis. (That this analysis is increasingly filled with trolling and contrarianism is a separate conversation). While I am now Bay-adjacent, I have been sufficiently disgusted with the Washington Football Team to avoid following any of the California teams).
I think the non-athletes commenting on athletes' performances debate (which I doubt is going away any time soon) is distinct from the battle over how much analytics matter in sports analysis. I feel if people do their research and can communicate it effectively, whether they played the game at a professional level doesn't contribute as much.
While I wouldn't be surprised to find that it's mostly non-athletes relying on analytics much more than athletes, there are many non-athlete commenters who have either resisted analytics entirely or don't consider it the be-all and end-all tool that many do. (This argument seems to break by age, with the older commenters less enamored of analytics than the younger set.)
It's tough to see how Garcia has a meaningful argument here. If he had a point to singling out Kimes' criticism of Garoppalo beyond Kimes' lack of playing experience, he didn't make it. You could make a stretch and suggest bias, as Kimes' has done local Rams preseason broadcasts (for those blissfully unaware, the 49ers are playing the Rams on Sunday). But it opens Garcia up to the same criticism, given he played for the 49ers.
I've only heard Kimes do football analysis, which I think she's very capable at. Had Garcia made a general complaint about people piling on Garoppalo, I'd have understood where he was coming from, but respectfully disagreed. It's not clear to me that Garoppalo has the kind of intangibles that help explain the teams success.
David