Sadly, the default values are an even bigger source of bugs. We just caught another one at $work where a field was never being filled in, but the default values made it look fine. It caused hidden failures later on.

It's an incredibly frustrating "feature" to deal with, and causes lots of problems in proto3.

You can still verify presence explicitly if you want, with the `has` methods.

But if you don't check, it should return a default value rather than null. You don't want your server to crash on bad input.