It's sad that it took legislation to make this happen, but I can see why.
I worked in a pseudo-Apple-store during the height of the 30-pin dock connector and I sold so many cases, speaker docks, charging cables, and all sorts of weird accessories that were built for the 30-pin connector.
Then Apple switched to Lightning. It was better in every. single. way. And yet people got burnt. There was so much hardware that was now incompatible that people understandably didn't recognise the benefits of the Lightning connector.
This mattered far less for other companies because of the lack of brand recognition. If someone switches from one non-Apple device to another non-Apple device, they don't necessarily expect to keep using the same cables, and back in the day every manufacturer had their own. The expectations of Apple were higher only because of that brand recognition.
Sadly, the fact that so many got burnt in the Lightning transition means that there is _still_, a decade later, a resentment among many. I've spoken to so many people who don't like Apple devices, who when asked why say things like "they're always changing their cables". It's obviously not true, but to most people who aren't familiar it might as well be.
I think this even burnt the MFI manufacturers. 30-pin compatible speaker docks and other accessories were very widely available, but there are far fewer devices made for Lightning. There are other factors here like the rise of Bluetooth and Wifi enabled devices, and the demise of the iPod, but I think manufacturers also knew customers didn't want Apple specific connector hardware anymore – I know I didn't.
Ironically, the long-delayed USB-C transition has probably had the opposite effect. In attempting to compensate for the public view of Apple changing connectors, they've become somewhat known as being the company with the wrong connectors. It's sad, given Apple's core role in defining the USB-C spec, but it's understandable.
I look forward to a USB-C iPhone. It's a shame it took legislation to make it happen, but I understand why given how long customers' memories are about the 30-pin connector. As much as we'd like to think USB-C was the "right answer" several years ago, it's a bit more complicated than that.