The shortly-to-be-released Mac OS Catalina will not run 32-bit programs.
Currently, we get a warning on Mojave systems, but can allow them to run.
In about two months, those of us who have to use their Macs for work purposes and have to upgrade OS, will be locked out of playing CoH again.
The only way I can think of to prevent this is to use an emulator running Mojave, but it's clunky, expensive, and may not work properly with the emulator getting in the way of the game.
So in this light, is it possible we'd ever see a 64-bit client...?
*edit: Homecoming Team have announced that it's better for no Mac users to have access, rather than for them to maintain the 32-bit version for Mac any more, even if we do find a way to keep running the current OS. Island Rum is being discontinued, and we Mac users are basically screwed.