Yes, there were over time, multiple teams working on intellij plugins to support google3 before it all got relatively merged.

You are talking, i believe, about the support for blaze builds in intellij, which was fairly early on, as you point out.

I suspect Laurent is remembering some of the google3 mobile/android efforts, which were much later.

This is just on the "java" side, too. There were other plugins being built that were fairly specific to google3 support.