It's hard to that this objection seriously. The publication is literally called the Financial Times. It's not exactly crazy for them to think that their readers might care about the entity that shows up the stock ticker rather than how the company happens to divide up things internally.

Even if it weren't a finance publication, I have trouble imagining you making this argument if a headline said something like "Google deals with outages in the cloud" because of the idea that it's misleading to refer to it as anything other than GCP. I think you're fundamentally not understanding how people communicate about this sort of thing if you actually think that someone saying "Amazon" is misleading in any meaningful way.