I think its all of the above. We still have pockets of the world that have yet to get 1 shot coverage across their populations, so maybe prioritize that first. Also seems to think it might be medically unnecessary except for vulnerable populations. Vaccines are not without some side effects and can create some non-zero amount of harm, which becomes a closer call with milder disease.
Personally I am wrestling with what to do with my college daughter - she had symptomatic COVID last spring, then was double vaxxed this summer, and now just tested positive again with basically zero symptoms. She also had mono last month. The idea that she needs a booster after being double vaxxed and twice infected in less than 12 months .... I would kind of like to give her immune system a break.