Comment 8 for bug 189462

I don't know what thread you were reading, but I didn't see anywhere in the conversation that you linked that slocate would be removed. The conversation focused mainly on the possibility of not shipping it by default in desktop installs. It didn't really even address server installations, nor did it at any point appear to reach a clear conclusion.

Regardless, just because something isn't part of the default install doesn't mean that it isn't supported any longer. The vast majority of the apt packages are not installed by default, but they're supported all the same. Any package whose maintainer is the Ubuntu Devs is bound to be kept up to some degree... if they really wanted to cease support for a product it would be removed altogether, which I've seen no evidence of.

mlocate has become preferable because the algorithm it uses to update its database is more efficient, resulting in less of a system penalty. It may or may not also be more well supported upstream (but I haven't checked lately).

In bash:
~# alias slocate='mlocate'