TBD doesn't mean you have a red CI main branch. Of course it is always green on main. It means you have short lived feature branch and rely on runtime checks for feature gating. A broken main will halt TBD. You are mischaracterize what TBD is.

From the linked Website:

> Depending on the team size, and the rate of commits, short-lived feature branches are used for code-review and build checking (CI). [...] Very small teams may commit direct to the trunk.

Indeed. That seems to be a new-ish addition. I'm glad they now admit alternate approaches.

I'm in the "continuously improve the team's process to best suit its needs" crowd.

Sometimes TBD is the answer, sometimes you need something else.

What I did notice is that, with time, mature teams end up simplifying processes in order to reduce friction and increase output.