[aniviacat]

It may be dangerous but it is an established pattern. There are many cases (like Cloudflare Pages) of others doing the same, hosting strangers' sites on subdomains of a dedicated domain (pages.dev for Cloudflare, immich.cloud for Immich).

By preventing newcomers from using this pattern, Google's system is flawed, severely stifling competition.

Of course, this is perfectly fine for Google.

[lucideer]

It is but this established pattern is well standardised & documented by the public suffix list project. There's generally two conventions followed for this pattern:

1. Use a separate dedicated domain (Immich didn't do this - they're now switching to one in response to this)

2. List the separate dedicated domain in the public suffix list. As far as I can tell Immich haven't mentioned this.