Surely a computer without internet would not have received the update?

But then would CrowdStrike stop the startup saying it requires network connectivity to initialize or something? Just wondering how invasive the app is

No, it'd boot up just fine without a network connection (as long as it didn't have this borked update).

How did it get broken then?

As in, does the OS require the internet so CrowdStrike can send telemetry data OR will it skip that step and just boot the OS like normal?

That would seem crazy. Maybe there is a crowdstrike onprem “master server” that is supposed to be available internally? Just spitballing, have no idea really