I think I'm now seeing why some people are so upset about this and I'm beginning to agree with them. Apple advertised a certain level of performance, a flagship level of performance, and six months later intentionally degraded that performance without notifying the owners.
I don't care if you are Apple, Samsung, Motorola, HTC, LG or OnePlus, if you charge flagship prices you need to deliver flagship performance through the life of the product. Anything less is dishonest.
It's like an auto manufacturer promising a certain level of fuel economy and issuing a firmware upgrade that degrades fuel economy so that the car can meet emission requirements.
I'm starting to think Apple might be in real trouble on this one.