I didn't say we would never support it. IMO It's a trickier subject than most people are giving it credit for.
Issues with dt at low framerates are a different problem. If the framerate is low enough to cause problems with gameplay, usually it is much lower than 30 FPS, so a framerate cap does not fix that. It's a separate problem.
Other game creation tools might provide a framerate setting, but I don't think that makes it a good idea!
Consoles are a different case: the hardware is known in detail in advance, so you may be able to say confidently that a game you have absolutely cannot run at vsync rate. However C2 games run everywhere from powerful desktops to weak phones. IMO a game running at half-vsync on a powerful desktop PC is both annoying and an inferior experience to a vsync-rate game. I didn't spend all that money on a ridiculous graphics card for 30 FPS :)
In short my opinion is that if a system can run a game at vsync rate, we should let it. Since there's probably not a really reliable way to detect the need for half-vsync rate and then accurately hit that, the best way to try and let it is to leave the framerate uncapped.