> the impact of your CI system itself being good or bad is tiny in comparison to everything in your end to end CI workflow.

I disagree here. A bad CI system makes it very, very easy to make the end to end workflow incredibly painful. Some small QOL features (buildkites input step was probably the reason it stuck for so long with us) are the difference between a tool being indistinguishable from others and being leaps and bounds ahead.

> it’s hard to justify the per seat pricing of buildkite

Buildkites pricing starts at 50% more than GitHub enterprise does. I couldn’t justify it as someone who loves buildkite and is in charge of making those decisions.

In most enterprises, the choice isn't Github vs Buildkite, it's Github vs Github plus Buildkite. That's what makes it so hard to pay for a separate CI vendor that costs more, when your source code hosting vendor already bundles one, as good or as bad as it might be.