[oefrha]

As a sibling has already pointed out, this blog post has nothing to do with “Google themselves”. In addition, “nothing really for end users” is obviously bullshit and inconsistent with what the post says itself, e.g.

> This means your existing proto3 projects can now use default field values and extensions.

proto3 not having required and default values was a big source of complaints, so supporting these indefinitely into the future with feature flags instead of having to be stuck forever on proto2 has to be a welcome change for a subset of users, at the very least.

[hot_gril]

Proto3 already got the required/optional feature added. I don't see why they couldn't have added default values too. (Personally I liked proto3 without optionals, defaults, extensions, etc, but it was a tough sell for people already used to proto2.)

[oefrha]

They can, and feature flags is one flexible (if somewhat verbose) way to do it.