Toot by RxBradRxBrad (mastodon.rxbrad.com)

The reason camel case is recommended when it comes to screen readers is because screen readers are incapable of determining when a word that's essentially two combined into one should nonetheless be pronounced as if it were two words. This would likely be a non-issue if users used something like underscores to separate words when composing hashtags, but that's not how things developed and so the camel case recommendation is an on-the-ground solution.

Toot by RxBradRxBrad (mastodon.rxbrad.com)

@imstilljeremy Speaking as a screen reader user, #dadjokes is in fact problematic. I had to read character by character to figure out exactly what it was. The only thing that might make it somehow less problematic would be that in the grand scheme of things it's an unimportant hashtag. But we don't decide whether or not something is or is not problematic in the accessibility field based on whether or not the content itself is important. And yes, Mastodon's UI fighting users on camel case absolutely sucks and is yet another user-hostile decision on the part of Mastodon dev.