Not trying to defend anyone here, but I wonder if there's a non-nefarious reason for this.

Specifically, there have been a lot of changes to cookies lately because malicious actors (malware/adware) figured out how to access the cookie store and infer/determine cookie information from other sites.

I suspect that maybe this cookie store is kept in a more secure part of the application and only the cookies relevant to the site you visit get pulled out of it. It may even be a risk to have the information for all domains even loaded into memory for the application.

With all that said, there should be some way to manage/introspect that cookie store from outside of the browser imho.