The real problem here is the nostalgia factor. A lot of people grew up having the planets ingrained into their brains with various mnemonics. Hard to say goodbye to “pizza”.
Now I'm curious: How publicised was Pluto's discovery in 1930? Did the public care? Would Earhart likely have learnt about it before she vanished in 1937?
They were basically calling it the great American scientific discovery at the time. Which is probably why some people were so loath to accept the "demotion."
Pluto was a planet, once. The crown jewel of the Plutonian Empire. But the Plutonians got greedy. They dug too deep in search of plutonium and awoke a terrible horror. Now all that's left of Pluto is a cloud of asteroids and a celestial dwarf, barren and uninhabitable.
The problem with Pluto being a planet is that we would also have to classify something like thousands of other objects as planets as well. That's the whole reason it's not classified as one anymore.