This was already discussed in the main thread. But I guess this already qualifies as a bug or at least bad taste, and is worth bringing up for attention here as well.
To get to the end-game phase (i.e. MIB moon mission, orbitals, alien moon missions, etc.) you have to get MIB commander and Ethereal commander. Either one can be tricky and dependent on RNG. But I think Ethereal commander is the most difficult one, because there is only one at Arbiter craft (and nowhere else on earth). And whether you can get one in the first place, and either manage to land it or shoot it down is very RNG-dependent. Further, while etherealRetaliation mission is clearly designed to provide a way to obtain the commander, if they spot your base and do retaliation run, they send a Dreadnought, not the Arbiter, so you won't get the commander in any case.
I think getting to the end-game is made excessively difficult and RNG-dependent and it would make sense to reconsider the requirements. For example, if ANY commander, rather than just ethereal commander, would unlock 'Alien-MIB communications', that would make it much more straightforward.
(As for MIB commander, you could get one if RNG throws MIB outpost at you, or if you anger the MIBs and they do a retaliation run against you. YMMV whether these are sufficient, because both heavily depend on RNG.)
See more in the tread concluding at:
https://openxcom.org/forum/index.php/topic,4595.msg158898.html#msg158898