"It’s not like you can get a Legacy base right now either."
True, but it's not like one needs a Legacy base to control any Lionel engine in command mode, at least those made in recent years. There is LionChief and/or Bluetooth for all new locos and that covers most or all important command functions using the $55 Universal Remote and/or the free app. I'm sure the wait on the Base 3 is frustrating for those without TMCC or Legacy bases.
Let's not turn this into a pointless discussion of which systems are most unavailable at present. Both Lionel and MTH high end command equipment are amongst the missing for a year or more now. Hopefully someone from MTH will eventually give us an update with delivery dates. We've been told the Base 3 will appear, most likely first quarter 2024, although they said end of 2023 is still possible.