The deal has been going on for a while, and I think the 5000+ tonnes is still on the table, but only for later (when the 4 upgraded Gabya are retired). The current plan is to replace 4 Yavuz class with 4 I class and 4 Gabya with another 4 I+ class. Meanwhile the Type 23 plan gets dropped.It is said that before the final decision, the navy lobbied for a 5000-ton ship, but they had to settle for the İstif class. They insistently wanted a ship that could sail into the ocean.
Note that TCG Anadolu and future AC flotillas need this multi-purpose frigate.
TN needs to evolve into (or adopt the doctrines of) a blue-water navy in order to become a navy beyond the Aegean and Eastern Mediterranean.Decisions of going from not being oceangoing to being oceangoing are political too as well as economical rather than being simply technical. I wonder if we will see more roadblocks when going to larger ships as we still get the engines from foreign vendors.