I think there's an element of them forcing an entirely new Google standard (then favouring it in their results) on to something they could just as easily punish (slow sites) directly.
Slow sites can be sped up quite often with small optimisations and improvements and those improvements can be guided by Google tools but instead they're forcing their own new format in the name of speed.
Slow sites can be sped up quite often with small optimisations and improvements and those improvements can be guided by Google tools but instead they're forcing their own new format in the name of speed.