I feel like most people in this forum hate everything about iOS 11 and talk about it constantly...(I like High Sierra too. I think it’s a fantastic release ¯\_(ツ)_/¯)
Because that's what a lot of people come here to do. They come here to complain. Some of them are just cranks who always have something negative to say, but most of them probably have legitimate complaints, but their numbers are not as big as they seem.
Every design change involves tradeoffs. There will be winners and losers. You make changes to a website that makes it easier for people to read on a mobile device, and the 5% of users who are clinging to their Motorola Razr phone and 21" Sony Tritron CRT will pull the pitchforks out. Percentage wise, the people who are haters is pretty small, but if they all seek out friendly confines to vent their displeasure, you get a lot of what you see here.
To be quite honest, on some days. I'm that guy. The people who think nothing good has ever happened since Snow Leopard are ridiculous, but how they feel isn't entirely foreign to me. Once in a while, I want to toss my iPhone in a lake and go back to having just a regular phone or even no phone at all.
A lot of those people have good reasons to be displeased, but some of them also need to understand that the world is passing them by.
And for the record, I neither love nor hate iOS 11. I couldn't tell you the difference between it and iOS 10 if my life depended on it. I've had some problems with High Sierra, but they were mostly minor and they've mostly been resolved... but I'm not a typical user and I've had problem with nearly every MacOS version upgrade so I expect that it's going to be a bumpy ride if I upgrade early. A lot of people expect the process to always be frictionless. It rarely is.