"My point is that time works against any value of tying these upcoming Atlas locomotives too closely to their old MTH roots. It seems more logical to equip these locomotives with what ever version of TMCC is current and slap them in Atlas boxes. The people that are going to purchase these locomotives are operators, not collectors. All they will care about is how it looks and how it runs. The color box will make no difference to them. Don't think 2021, think ahead to 2023 or 2024."
IMO, it would be foolish for Atlas to tie itself to the old and defunct MTH company. Why do that? Atlas has an established O gauge rep (for better generally, and for worse occasionally). The new "Atlas" locs will be that: Atlas locs with whatever remote system Atlas installs. In my case, if it's DCS, then I won't buy. If it's TMCC -- or a newly licensed Legacy-driven loc (nobody has mentioned the possibility that Lionel might license Legacy given the changing hobby), then I may just buy.
Atlas will be thinking ahead to 2024 ... and beyond ... and establishing a market for their new locs probably in the current Atlas box-color scheme.