Yes—recent visitors say Taq Kasra is still worth visiting. In a recent visit shared by travelers (November), the main arch was not covered by scaffolding. There is typically a perimeter fence, but you can often walk around it and still get clear views and photos from multiple angles.
For the smoothest visit, consider going with a licensed local guide/driver. Conditions can change, so if you’re traveling soon, confirm the latest access situation locally before you go.