"BDDK, the Turkish authority in charge of regulating and licensing banking and payment systems across all electronic or conventional platforms, has repeatedly refused to grant operation licence to the US-based company despite all the efforts, PayPal Turkey explained in the statement."
Despite the what effort? It was obvious this is coming. Turkish financial system has lots of regulations after 2001 economic crisis. Paypal should get the banking licence to operate. This includes physical servers located in Turkey, accessing data by authorities, taxing on transaction and etc.
Paypal didn't apply any of these items. Maybe Turkish market is not big enough for them to invest on these regulations.
I have started a fintech startup in Turkey (similar to Stripe) but before we launch, regulation changed and to run a payment gateway, you should have at least 5M TRY invested in the business. So yes regulation exists and bad for startups and small businesses but for business like Paypal it's not about "effort".