Yeah when we first started, "code review" was a weekly meeting of pretty much the entire dev team (maybe 10 people). Not all commits were reviewed, it was random and the developer would be notified a couple of days in advance that his code was chosen for review so that he could prepare to demo and defend it.

Wow, that's a very arbitrary practice: do you remember roughly when was that?

I was in a team in 2006 where we did the regular, 2-approve-code-reviews-per-change-proposal (along with fully integrated CI/CD, some of it through signed email but not full diffs like Linux patchsets, but only "commands" what branch to merge where).

Around that time frame. We had CI and if you broke the build or tests failed it was your job to drop anything else you were doing and fix it. Nothing reached the review stage unless it could build and pass unit tests.

Right, we already had both: pre-review build & test runs, and pre-merge CI (this actually ran on a temp, merged branch).

This was still practice at $BIG_FINANCE in the couple of years just before covid, although by that point such team reviews were reducing in importance and prominence.