It seems a bit nuts that people are chasing Standard Model extensions for dark energy but they haven't even resolved particle with gravity yet, or has there bee

It seems a bit nuts that people are chasing Standard Model extensions for dark energy but they haven't even resolved particle with gravity yet, or has there been recent advances? I never heard of string theory being somewhat formally accepted. Hm, now they have things like "loop gravity". I guess they are still trying to crack that nut. At least we can measure gravity in a local/controlled setting...