You're 100% correct about assessing the conditions and the gravity of guerilla warfare, but I don't think any of the extant maoist movements have made presumptions about their progress. The Naxals and CPP-NPA didn't launch their PPWs on a whim and while there's discussions to be had about the length of their PPWs the fact they haven't lost yet is notable when you compare them to how the PCP waned after Gonzalo's arrest. Even the underground group behind Austin Red Guard never had delusions that they were ready to launch a people's war.

Cuba, Vietnam, and Korea were/are not MLMaoist because MLM did not exist at the time and they don't identify as such now, so Maoists don't claim them when discussing the international Maoist movement. That's why the PCP, CPP, CPN, CPI(m), TKP/ML, etc gets brought up as common examples, because those are parties that directly contributed to the development of MLM and have adopted it as their ideology. Also Maoism is more than just PPW (and even that is still in debate), so Cuba, Vietnam, Korea, etc are all contextualized as part of the MLM continuity, but not as examples of the ideology which evolved after them.

The average Maoist is not an 18 year old white college student, they are from the third world of various ages and backgrounds. I think it's extremely dismissive of ongoing communist movements to call them romanticist and idealizing struggle after stating how heavily revolution weighs on you while people are choosing to continue their revolutions. If you're talking about your perception of western Maoists, sure, there's probably a fair number of MLM romanticists same as there are in anarchist and ML circles. I don't think it's fair to tar one particular tendency with something that's symptomatic of all western leftists to some degree.