The banned list proves that context matters more than having the newest tools. These features work well for small apps but they cause problems in a project this size.

IIRC a big part of Google’s coding guidelines is also about making it easy for people not heavily invested in a specific language to contribute safely. So not necessarily a project size but rather an organizational concern.

They’d rather see it done the same way it would’ve been in any other similar language than with a language specific feature.

There are also portability concerns in mind given that projects like Chromium have to be easily portable across a vast amount of platforms (this shows with things like long long which is also on the list).

Agreed. I also prefer conformity over sporadic use of new features going against an already set of standards in a codebase. it's overall less cognitive load on whoever is reading it imho.

Some of it is historical reasons or portability more than anything else. Chrome is an old C++ project and evolved many of its own versions of functionality before standardization; and there's benefit to staying on its own implementations rather than switching.