Interesting how this topic took off. Must be a lot of you using this technology to create comments.
There are 2 sides to this coin:
#1 People who have existing infrastructure and trains (they have a TMCC or Legacy base and remote set, possibly even LCS modules and equipment, existing engines and accessories). To them, the CAB3 needs to represent an upgrade in capabilities that they care about to justify the cost ($500 list) and the fact that then it replicates and makes their existing equipment now obsolete or redundant.
#2 people just starting out, or wanting to go command, and missed the boat so to say on the 990 Legacy set or Cab1L set, and this is what Lionel is advertising and selling as a very limited option.
So yes, people who have TMCC Legacy and those to desire to get TMCC or Legacy.
Conventional operators, well are you going to buy a CAB3 base, so you can use a Legacy powermaster. so you can drive a conventional engine with your phone?
You can, but that's a chunk of change to make that work.