Hide Online status in users list or disable the feature?

That's a good idea, I think it's needed, for other reasons too (e.g. privacy). — There isn't, right now, but this CSS seems to work (tested in Dev Tools) as a temporary workaround:

.esCtxbar_list:has(.esPresence)::before {
    content: "This users list is disabled for now";
}

.esCtxbar_list:has(.esPresence) > div {
    display: none;
}

That is, removes the list, and adds a message — there doesn't seem to be a good way to hide the "Users" right sidebar tab button.

Edit: I changed this topic to an Idea, and Planning-to-do.

Implementation wise, there could be another checkbox on one's privacy preferences page, here:

https://forum address/-/users/  my_username  /preferences/privacy

Maybe with a checkbox title like [ ] Don't show if I'm currently online or not
or maybe [ ] Hide my online presence but I wonder if that's harder to understand, hmm