And soon to be Reddit's story with their pending redesign which removes all CSS from subreddits among other things that only serve advertisers rather than the community.
We’re designing a new set of tools to address the challenges with CSS but continue to allow communities to express their identities. These tools will allow moderators to select customization options for key areas of their subreddit across platforms. For example, header images and flair colors will be rendered correctly on desktop and mobile.
We know great things happen when we give users as much flexibility as possible. The menu of options we’ll provide for customization is still being determined. Our starting point is to replicate as many of the existing uses that already exist, and to expand beyond as we evolve.
Sounds like they're trying to keep the same flexibility as the existing CSS options, which is a bit different than removing styling.
Meh, it's time someone knocked them off their perch. It's the same with all these platforms. They all degrade after a few years. Their priorities change from providing a valuable service to squeezing every red cent they can out of their platform. That was probably always the plan but as soon as your agenda switches away from providing for your users, you're trash and it's just a function of time before people start jumping ship.
As far as I can tell, the custom CSS is holding reddit back from any type of optimization/modernization of the HTML markup. Removing it and adding other customization options could actually improve the experience while still allowing subreddits to make changes.