I was referring to the forum revolt that would have happened had they tried copying Apple (see: Pixel, limiting choice, etc) back in 2011 when AOSP And Holo UI was all the rage. The mere idea of losing many features that were considered staples of Android then would have been blasphemy. I was not referring to losing UMS but I sure would have revolted. I didn't need no stinking drivers to mount UMS but I couldn't locate the software necessary to mount MTP and my cars never worked via USB anymore. To me it was a huge inconvenience. I'm a stick in the mud, and when I get used to doing things a specific way, forcing me to re-learn and re-adapt to a new way out of the blue for no reason just makes me want to stop giving you my business. I do not take kindly to frustration and unnecessary change.
I can't imagine living without the SD card. The mere convenience of having all your data instantly available (like my 3K songs) when switching devices is too good to lose. It could take hours to re-download all the data on my SD card from any 'cloud'. This includes backed up APKs since 2009, MP3 files, all the photos I've taken, podcasts, videos, etc. Heck, I got 20GBs used right now of old YouTube content archived that's long-purged from their site today.
Also, if my phone were busted, that data would be lost forever. With an SD card, I can still retrieve it. Even if the card goes read-only I can still access it.
I'm still miffed we lost IR blasters, removable batteries, and notification LEDs. Given I'm an A-Series Samsung user today, I'm sure the headphone jack is next ultimately, but I'm not planning on buying another new phone unless they get rid of LTE and VoLTE for say, 8G in like 2050 or something.