From a safety perspective, I see no reason why those would have qualified to receive the less capable FSD beta in December should not receive the current version. The recent version is significantly better than the version from the last intake of testers. For this reason, I believe that the engineering team likey is not wanting more testers and the lawyers/insurance group is not wanting to add the liability until the product risk (disengagement rate) becomes significantly better.I hate to be a contrarian, but IMO, his not releasing FSD Beta to more people is about the only decision he's made recently that I actually agree with... it's just not ready.
All above is my pure speculation, though I believe it is a logical explanation why people with 99+ safety scores have not been added to the tester group.