Hi Thomas,
Please note this is just my opinion, I don't work for ESRI, I am just a user like you:
This is one point where I unfortunately do not agree with your "simple" conclusion. The problem is, there are simply two types of ArcGIS users and organizational workflows: some WANT relative paths always, others DON'T (like the OP here), and both groups tend to have strong opinions about this.
ESRI actually probably decided to change the default based on numerous requests on the Forums and ArcGIS Ideas. E.g., see this strong plea for having relative paths as default instead of absolute ones:
For the love of god, make "Relative Paths for data source" the installation default.
For the love of god, make "Relative Paths for d... | GeoNet
I think the title speaks for itself... just like there are many adepts for absolute paths here in this thread, there are many organizations who have setups that actually benefit from having relative paths by default, even if this seems alien to the opposite group.
That said, given this situation, the only logical conclusion for ESRI should be to support both workflows... Keeping the "relative paths default", that means indeed implementing an "absolute path" option, so that users can switch the behavior of ArcGIS Pro at will and adjust for their organization's workflows.
Switching the default back to absolute paths would be senseless given the described situation.