In a perfect world, you can scale CI indefinitely. However, I don't think it's a simple as that. As mentioned in the post, even with a hermetic build system your CI times become entwined with your dependency graph, no matter if you're able to shard it over remote executors or not.

The block you've quoted specifically mentions gating _merges_. I still think its prudent to run ~all tests after merge, with automatic reverts if tests start failing. I really want to make sure that people think of CI, merges, and deploys as pieces of a larger puzzle and not a monolith.

I updated the language around this in [0], hope that makes it clearer as to my intention.

[0]: https://github.com/felixmulder/felixmulder.github.io/commit/...