Anecdotal, small sample size, but recently Opus 4.8 just generated something very stupid, where as previously it was mostly okay (at least for intermediate things) and Fable 5 seemed totally sharp. (At least on par with Opus 4.8)

Are they degrading Opus to then make a future Fable seem actually better (after it's been possibly weakened?)

At the bare minimum we need some real laws that prevent companies from crippling products without telling us. Maybe there's already legal precedent for this.