If it does have supersonic speed, what is stopping h-20 from also carrying BVR missiles like PL-17 and also carry a big radar. That way they can self escort. Essentially an even bigger version of J-36, launching AA missiles, carrying big radar, acting as an AWACS, directing drones. The only thing it will lack is maneuverability, but that can be mitigated by staying far behind. Essentially a huge missile truck. Such a platform will be very useful.
Following up on my earlier conjecture, I wonder if the H-20 wasn't originally intended to be supersonic, but after the Russia-Ukraine conflict started, the relatively good performance of the Tu-160 convinced XAC/PLAAF that supercruise + stealth is needed for a next gen bomber.