A lot of people would agree with that. Wilkinsburg has a proposal to merge with Pittsburgh:

https://wilkinsburgmerger.org/

There is a lot of consolidation of services with Pittsburgh in Allegheny County that don't include annexation. Waste disposal and policing in particular. EMS, not so much. IIRC, a lot of municipalities in Allegheny County maintain their own volunteer fire dept.

Also, this is such a great question. Have you checked in with r/urbanplanning to discuss the classification issue? I worked for a small neighborhood association for a few years, and we were qualified for certain CDBG grants because of our demographics. I am sure that there are other economic opportunities that are offered to 1st class tiers that aren't offered to all classes. Some of those would be infrastructure opportunities, like airports, interstate roads, and consumer rail development.