"I have a feeling, TMCC is going the way of PS-1. "
I don't see it that way. TMCC is command control with the added potential for pretty good quality sound. It's forward compatible with Legacy.
PS1 was not command control and thus had no real compatibility with DCS or other command systems. I'm pretty sure no one was doing PS1 "upgrades" or retrofits once PS2 became available. Indeed, I don't recall anyone doing PS1 "upgrades" or retrofits in any significant numbers except for repairs for folks who didn't want TMCC upgrades during the 1995-2002 period when TMCC was the only game in town.
Howard Hitchcock has gone on record that Lionel is working on developing technology that will allow the next generation controller (whether it be a handheld and/or smart device) to communicate with, obviously, Bluetooth locos, LionChief locos, and backward compatible with Legacy/TMCC locos. If they can come up with such a device, upgrade or a bridge, TMCC potentially will never become obsolete in the foreseeable future. A device that allowed a Bluetooth command structure to talk with a TMCC/Legacy receiver is one conceivable path forward. They have a vested interest in not obsoleting 25 years of products, as Hitchcock noted in his Notch 6 interview.
