Buybacks are a tax dodge. Nothing else. Dividends are the proper way to pay out excess cash the enterprise generates. Society decided how much to tax such distributions, and a certain class of people didn't like paying even that laughably small share.

Buybacks were justified by a whole lot of things that simply are outright lies. Take away the tax benefit and you'd see them go away overnight.

Discussions on the morality of buybacks are unrelated to the question of whether or not Apple’s ratio of R&D to buybacks (and dividends, which are also referenced in the filing) indicates lack of confidence in the company’s prospects.

Dividends are taxed directly and generally aren't tied to CEO compensation, unlike buybacks. Buybacks are more a sign of management incentive structure.

The filing references dividends in addition to buybacks, stating that their ratio to R&D indicates anti-competitive behavior.

Confidence and maturation, or stagnation? I can see good arguments being made for both directions.