Their Twitter feed says there's a submarine cable cut.
If one cable is cut (and only one website corroborates this information, and that says the cut is in Vietnam... our traffic goes the "other way"), then why are the remaining 3 or 4 cables idle?
I don't think this issue has happened with Transworld. Additionally, I think PTCL has put their residential broadband connections on one cable (I may be COMPLETELY wrong, but this is what it feels like) and God forbid, if this cable is cut. But either way, what about the other three cables? What's the point of redundancy if they're not doing their job?!
Can others (Nayatel, Stormfiber, Optix etc.) comment if they're facing slow browsing as well? Can you do traceroutes to random servers and check if the issue persists, please?