If you were early at Google it means more as going through that hypergrowth was very difficult and there was less dead weight. But for the last 10 years Google means essentially two things from a hiring manager's perspective: 1) you have decent floor of basic technical ability as no one stupid or a complete faker makes it through the technical interviews (but note it's a low floor as anybody with 100 IQ and reasonably technical mind can probably brute force their way to passing if they want it bad enough) and 2) if you were successful there you can deal well with large-scale system complexity and (likely) the politics of working with many partner teams and stakeholders. It's not foolproof as any given individual, role or team could get lucky in terms of having relatively high agency and fewer dependencies, but on balance anyone L5+ is going to have to deal with a fair amount of that.

Given the 15 years of essentially unconstrained growth and moats from any real competition, I think your assessment is largely correct though. The name brand reputation of Google far outweighs the likely strength of any given candidate, especially if you expect execution without limitless resources and industry-leading technical mentors/gatekeepers at every critical juncture.

The reputation of ex Googlers was established in the early days when they were tremendously productive, the bar was genuinely very high and turnover was tiny so there were very xooglers to begin with and they were mostly founding startups.

Over time Google grew an enormous amount. Productivity dropped through the floor due to endless headcount expansion, the bar did get lower and "I was at Google for two years" became a much more common thing to hear. But first impressions stick so Google still had done of that early day mystique.

Source: was at Google 8 years, early days, still have friends who work there. Saw the changes with my own eyes.

I did not come away with anything from the story that would make me have a negative opinion on author's technical capability.