Update: I found the thread, https://orgmode.org/list/87lf90b5ey.fsf@gnu.org/

Timothy <tecosaur@gmail.com> writes:

> Regarding the Emacs 24.3 requirement, I haven't got the thread on hand
> but IIRC Bastien said that he will bump Org's minimum Emacs to 25 in the
> 9.5 release. As long as I'm not mis-remembering, the above should be
> fine.