People didn't mind when IE was muscling in and adding useful new features. They abandoned Netscape because the features made the web better. It wasn't until they stopped adding features to the browser itself that it really started to become a problem. They would still add features, but too much relied on ActiveX -- which wasn't necessarily evil, there's a grand vision there of component re-use across the OS and varied applications, the same was done with Java Applets and even Shockwave/Flash, but it sucked more and they were all plagued with security problems. Then MS stopped innovating pretty much entirely, and wouldn't even play catch up for a long time, whether with their out-of-browser plugins (oh Silverlight...) or the browser itself. No support for tabs for a long time, or popup blocking (later ad blocking), they had terrible performance... And as various "web standards" advanced to make things nicer for the users and developers, and add capabilities that didn't require an external plugin, they drug their heels on that too.

Eventually, the hell that was IE was a combination of hostile user experience, security problems, performance problems, and developer pain in finding workarounds or other support because it was so far behind on everything. It had nothing to do with their power to dictate or experiment with new features. The extent of the hostile user experience that leaked outside the browser itself was the "only works on IE" problem that forced people to use IE for that site, on the whole it was comparable to the "only works with Flash or Java applets" problems and not as bad as the experience of the browser itself. For the most part these days, the two parts of that hell that remain relevant are the hostile user experience and the developer pains parts, and Mobile Safari is the successor to both for over a decade now. No one supports IE11 anymore (let alone older IEs) but they still have to support Mobile Safari. I have fonder memories of dealing with IE11 (and earlier) support/workarounds over Mobile Safari's crap. My view is more power to actual Chromium-based browsers on mobile even if I personally use Firefox on PC and android despite their user experience shortcomings (at least they're not very hostile). The only part of hell I'd be worried about is that of a hostile user experience, which can be worked around by individual users if they are allowed choices.