The F-15s are great, but they are 4th generational fighters.
The Air Force should be upgrading to F-22 Raptors that are 5th generational fighters that can do more and have less down time between flights.
From what I have read, all the manufacturing templates, jigs and fixtures necessary to build the F-22 were scrapped and no longer in existence......................
33 of the oldest F-22s are due to be retired beginning in 2023, and the entire type are going to be replaced by the NGAD (Next Generation Air Dominance) aircraft currently in development.
Buying new F-22s is not an option, as the tooling has been destroyed. It was preserved for a time after the line shut down in case Congress wanted to open it up again, but instead chose to launch the NGAD program.
The Air Force can buy F-15EXs because the Boeing (McDonnel) F-15 production line is still actively cranking out F-15s for sale worldwide.
The F-22 is no longer in production. Restarting the line would be prohibitively time consuming and costly. Meanwhile, the newer F-35 has limited production that prevents a major increase in numbers byond what is schedule. This makes a batch of new, upgraded F-15s a good way to increase US combat airpower.