I have never had a problem with E10 in my life and I am older than dirt. My lawn tractor and Z turn are 99 models and neither one has had the carb apart. They along with the weed eater and leaf blower sit all winter and fire right up in the spring.
My gallon can of pre mix for the two strokes sets all winter and I never throw it away.
I have a trailer queen tractor. I drain the gas once a year and put it in my kawasaki Z and it gobbles it down like smooth whiskey.
As far as I am concerned it is urban legend that covers up for other problems. I do not run an outboard anymore so no comment there.
I do treat the gas with some stabil and 2 cycle oil before the cold winter snooze.