Why would it though? If they can source an engine from somewhere, they should be able to build the rest in a decade. It's much easier to design and build 5th gen aircraft today then it was at the time the Raptor was built. If they can even get to 80% of the Raptor, that's a decent 5th gen platform. Of course, by the time the TFX would be flying, 6th gen prototypes would already be flying as well in NATO and probably China as well (albeit, probably with a 5th gen level engine.) The biggest challenge (and achievement) in a fighter is the engine. If you can side-step that hurdle entirely, as countries like Sweden do, the rest you can get away with.
With that said, if Turkey's strategic goal is to truly be independent, then it should also be laying the industrial foundation to build its own powerplants. The TFX with an imported motor is not enough to complete that objective.
Simply since nothing fits. Timeframe/schedule, performance & cost, ...
- They claim a fighter in dimensions and performances in the league above the F-15 but have so far built not a single own aircraft type.
- assembling in licence or manufacturing as a subcontractor give you at best some expertise but not all they need.
- They want to do this by a schedule that is plain impossible even for countries with much larger experience.
- They want to accomplish this all with a budget that is plain unrealistic.
- They want to use F110 engines for the prototypes but neither GE has confirmed this use (quite uncommon in comparison to other similar cases) nor the USA (which is a mandatory MUST).
- They want to replace these engines for the following prototypes with a clean-sheet engine, that is not even specified, after RR bailed out due to unrealistic demands on ToT and in a time much lesser any country with vastly more experience in engine design.
They simply have ZERO experience especially in such a sophisticated engine (just look; The Altai's powerpack is still a failure, the small turboshaft for the small helicopter has just begun with its first test and besides assembling F110s for GE, there is no technical base) Just see how Russia struggled with their Izd.30 engine, how China fights for the WS-15 ...) As such, a comparable engine on their own in 2028 as they claim is PLAIN IMPOSSIBLE and so how will they roll out a prototype next year when design is not even finished. Just look at the KFX?
In fact, nothing fits and they know it ... it is nothing but a hoax.