OK, I'm not sure if this is perfect of overstretching the analogy, but I love it.4e FR does have its fans, but it certainly wasn't popular compared to the 1e–3.5e version of FR. But that gets to the difficulty with your ice cream analogy. WotC went about building 5e very deliberately in response to what they believed D&D fans (including the ones they had lost as active players thanks to 4e) wanted. And that includes selecting FR as the default setting: even after the debacle* of 4e, their market research indicated that FR was still their most popular setting by a wide margin, especially the pre-4e version of FR.
So a better analogy would be that the ice cream parlor used to offer a dozen flavors but has decided for economic reasons that they can now only afford to offer one. So they switch to vanilla-only because far more customers prefer vanilla than any other single flavor, but then some ice cream preachers start ranting on their doorstep about how delicious ice cream is and live-streaming themselves licking various weird-looking scoops and the parlor starts to sell a ton of vanilla, more than they ever dreamed possible, and then a gazillion more people show up demanding raw ice cream ingredients to cook up their own bizarre flavors, and suddenly the parlor is obscenely rich and can offer all their old flavors and then some, and everybody's happy except the people who hate the old flavors, and also the vanilla fetishists who are pissed off the parlor only has ten open tubs of vanilla rather than a hundred tubs like they used to in the good old days.
*(in terms of sales, not necessarily in terms of quality of game design; I'm talking about why WotC did what they did, not edition-warring)