PHPStan will verify that these matches cover all cases, which guarantees that all cases will be covered.
In addition, if PHPStan is not used, the constructors will immediately bail out when they hit a case that isn't covered.
The only downside is the extra indentation :(
to be consistent, these shouldn't be exposed in the API like this...
I'm not very happy with the whole 'type ID map' paradigm (particularly its lack of static analysis guarantees), but the most important thing right now is to get this stuff out of the API so that plugin devs don't try and abuse it. We're not going to change the whole system days before PM5 release.
