The F-35 simply has a different role within the U.S. and NATO forces. Due to its stealth capabilities and sensor fusion, the F-35 is considered a superior asset against all 4.5+ generation models; through its “First Look First Shoot” BVR doctrine, it is a “4.5+ Generation Killer.” Ultimately, however, it is a Gen 5+ multi-role fighter that is limited both kinetically and by its range when facing Gen 5+ air superiority fighters.
Assuming the opposing fighters are at least Gen 5+. Turkey could exert significant pressure with the TAI KAAN, even as an early Gen 5 aircraft in the Block 10 version. I don’t believe we’ll ever reach the Americans’ level in stealth and sensor fusion; due solely to their experience, know-how, and technology, there’s a gap of at least 10+ years, and they have the best subcomponents in the aircraft—that’s simply a fact. The problem is that the F-35 can’t be scaled cost-effectively; even if the KAAN, as a Gen 5.5+ aircraft starting in 2035+, achieves only 70–80% of the performance of an F-35/F-22, this is sufficient to exert pressure, as Turkey produces it at cost and can manufacture 250–300 units for domestic use if absolutely necessary.
Add to this effectors like Kizilelma, Anka 3, and Super Simsek.
The remaining NATO countries must purchase the F-35 and effectors from USA at a high cost and wait.
For most European nations, the limit is already 40–60 aircraft because maintenance is simply too expensive. The only exceptions would be the U.S. and Israel, which have unlimited resources.