Many googlers use brew to install applications on their laptops. This not against policy. Other googlers work with code stored directly on their laptop. There may even be developers who are obtaining deps (for their own builds) from brew.
The problem with the brew author is that he had every opportunity to make himself look hirable at Google but instead chose to write an incorrect screed and publish it on the internet.
At the time I used brew (5 years ago) it didn't require a santa exception with business justfication (and my justification would have been "I need this for my work"). Fortunately this wasn't really a problem for me any way as I don't even look at Mac machines as anything other than a thin client.
But, as usual for internet discussions, it is fun to rathole on side conversations.
No one’s running Xcode on the web or on a Linux machine.
I'll admit that surprises me greatly, I can't see why it's considered more efficient, but hey, Google.
A poor little laptop would break down and cry.
I believe that there are also a bunch of IP reasons for this policy, but from a practical perspective doing everything with citc and blaze is really the only option.
The folks developing Chrome for Windows or iOS apps might have different workflows, but even then they aren't going to be using brew because of Google's third party code policies.
But 99.9% of the builds happen remotely. So local vs remote code just isn’t that relevant.
It is also true that Google spends millions and millions on its dev environment every year, so this isn’t your average “no code on laptops” situation.