I also spend alot of time reading here, but I somehow manage to miss some really crucial topics. This new feature completely snuck up on me too and the first I heard of it was in this topic. Thanks @HAWK for bringing it to our attention! I'm now exploring it with my moderator team to decide whether to keep it enabled or not.
Maybe the discourse team could try to be a little more vigilant about notifying all of us (and esp their paying customers) of new features that will be "imposed" on our communities that may need to be disabled.
That said, I am deeply grateful to the discourse team for their continued and diligent work to develop and evolve this amazing software, and I am really happy with it and with the velocity and scope of improvements. I have no complaints at all about the direction and have full trust in discourse, and am crazy impressed every day with what's happening with the software.
Also, I'm not a paying customer, so am very willing to accept the way changes appear via an ongoing flood of git commits and that frequently one rebuild of my site spawns a series of rebuilds over the next few days as new features get tweaked and bugs get fixed. It's fun (in an easter egg hunt sort of way) to look for changes and new features, and to report bugs and see them get fixed quickly. I can probably count on one hand or even with just a few fingers the number of times I had an unpleasant surprise after an update. Even then it was not a big deal and was quickly resolved. Nary a complaint from my community.
I'd be sad if the pace and creativity of the improvements slowed down because the team has to second guess every new feature and spend more time looking backwards and worrying excessively about the impact on the existing installs.
I think the answer for me will be to watch the #feature category so I am notified of every new post in that category, even if it means some extra notifications about feature requests that I don't need to see.