I remember hearing somewhere that the problem might be storage. as PGM requires a higher infrastructure standard than dumb bombs. in the long term that would not be an issue of course. as well PLAAF seems to have a lot more A2G missiles than PGBs, KD88 and KD63 are regularly seen.The Chinese aerospace industry has a wide variety of PGMs produced and tested, including multiple SDB equivalents.
The PLA doesn't have any in service to our knowledge, which is an entirely separate problem.
As for 250kg bombs on dual racks, they absolutely have dual racks able to carry two 250kg bombs, (see pictures in my post history), the issue is they don't have any 250kg PGMs in service.