The problem is the feel of the keyboard is different, and there's a lot of speculative consumers out there. People want to love Apple because, Apple. People walk in to a store and touch it and immediately feel a difference, then think it's terrible which satisfies their desire. They want one, but can't justify it, so the keyboards naff, that's why I don't have it.
Truth be told people absolutely love the keyboard. After using it for a couple of weeks myself it felt like night and day going back to an older keyboard. I used to think my old keyboard was the best around, after using this new machine it's really hard to go back.
There are a lot of office typers out there too, people with huge travel old style Microsoft keyboards at the office PC. If you've come from that to a shallow laptop keyboard it will feel really odd at first, as it's going from one extreme to the other. So if you're used to high travel keyboards and are smashing this thing hamfisted then you're going to have a bad time. If you're a softer typer whose used to laptop or low travel keyboards then you'll be fine.
Either way perpetrating this illusion that it's a marmite issue of 50% love/hate is nonsense. I'm not doubting there's people out there who genuinely hate it (For whatever reason), but it's more like 1%.
You can have your reasons, nobody is sticking up for the machine because it's Apple, it's genuinely a really good keyboard. It feels like a quick responsive mechanical keyboard, I can type a lot faster on it with the larger keys and because it's so low travel they snap back instantly.
The only potential issue I can see with it is feedback, I touch type so it's not a problem, but I can see an issue if you need to look at it perhaps. But this is made for the mass modern market after all.
I've yet to see a genuine complaint though, it is as others have pointed out the occasional person who doesn't own one making a comment. Or people saying they keep hitting the TB, and one or two who say they rest their hands on the keyboard? I rest my fingers on F/J where their meant to be, don't have an issue.