I think that is just how it is.
As we know, Turkey has an incredibly high inflation rate and whereas most governments, and economists, seem to think that the way to cure inflation is to increase interest rates, I have read that Erdogen believes the opposite. He thinks that if inflation is high then reducing interest rates will help.
There is an argument for that, but it is not one shared by the majority of economists.
He reduced rates when the Turkish inflation rate really started to take off, and certainly it has not improved. So, the rates you quoted for time deposits are, in my opinion, just how it is at the moment.