Which the US would have been willing to give... if they didn't cozy up to the Russians for S-300 and S-400s.
They also wanted F-35s, not just F-16s. That's not one to sell unless you're 100% confident they won't copy it for their own domestic production, or sell it to, say, the Russians. And modern Turkey is looking a little shaky in that regard (no, not an earthquake joke).