I think they make what the government buys.
The F-22 is clearly superior to the F-35.
But, I believe that there is an unmanned aircraft waiting in the wings. Which can take down any manned aircraft.
Both are designed for a different role. However, depending on who's flying, the aircraft could become irrelevant with any of the previously mentioned models.
You are correct, though, concerning the UCAV. Its development will have an impact on many roles like defense suppression, strike, and interception. If developed properly, it would likely outperform any manned aircraft, given it would be capable of maneuvers not possible by a human pilot.
I certainly hope so, but the 'wings' could be 20 to 50 years before the thing is sufficiently autonomous that it can fight without an active datalink. That is roughly the lifespan of a fighter aircraft type.