Some more thoughts about Yoda and his relationship with the Rebellion:
Overthinking this a bit, I guess I have to agree that it makes very little sense that Yoda isn’t more actively involved with the Rebellion. Sure, he’s not a warrior like he was in the Prequels - but so what? He’s a Jedi with the ability to see the future (at least partially). He could be an invaluable asset for Rebel military intelligence. They could ask him to use the Force to ascertain the probability that some mission will succeed or fail, or use the Force to predict what the Imperials will do in certain situations. The ability to see the future (even if it’s not 100% reliable) would be invaluable in terms of military strategy and intelligence gathering.
But this is supposed to be a fantasy and Yoda is an archetype: he’s the wise master that lives in a remote location and will semi-reluctantly train those who are willing to learn.
That is an interesting take and thought exercise ^, although isn’t that the fault of the Prequels, more than a dislike of the OT, in not giving us (or Yoda) a valid reason for him to be hiding in isolation on Dagobah all that time?
Having Yoda immediately exile himself to Dagobah after his brief fight ending in a draw against the Emperor, with no attempt at rescuing or helping other surviving Jedi, or even trying to thwart the Empire (in effect letting the Sith rule the galaxy for 20 years plus, before reluctantly training Luke for a short time), does certainly bring up some issues!
^ - I also find these thought exercises invading my mind and time even after all these years! Must be a holdover from all the time spent piecing information and guessing how it the story could play out in the Prequel stories (before the Prequels were ever released).