The last time we lifted the level cap was in 2015. In 2014, we added a unilateral close-as-duplicate power for gold tag badge holders, but no new reputation level. So we've been thinking about giving users more reasons to keep playing. (I've answered this question with some circumstantial evidence that people do begin losing enthusiasm after they hit 10k.)
Please answer with a description of the privilege you think would be worthy of 30k and include your arguments after a horizontal line (
\n---\n). These should be on-site unlockables and not physical items. Proposals don't necessarily have to give users extra powers on the site, but they should feel significant to those who have achieved this impressive level of reputation.
I left an answer to be an example. I've had a significant head start over most everyone else thinking about this feature, so please don't worry that your idea is underbaked. That said, the most useful answers will include justifications more than "wouldn't it be cool if . . ."
Finally, let me be the first to point out how odd it is that I am proposing a new extrinsic motivation. It turns out that one of the great pleasures of this job is that I can do a small part in helping many other people enjoy writing great posts. I believe that a well-considered additional privilege level will benefit many users across the network. This is doubly true if that privilege empowers more people to solve problems and fix annoyances they come across.