Until Mirai works on the PCS aspects of her skating, she will not score 140+ in Russia or any other country.
Back at the 2015 Rostelecom Cup, Evgenia M. may have only had one 1 GP win under her belt, but she was the reigning World Junior Champ and had been dominant on that scene - she set the precedent for the Zavigota treatment this season. Alaine, while a "top" Canadian lady, was only a "top" lady given the relative lack of competition in Canada - leading up to the 2015 Rostelecom Cup, her international scores had been decimated by Evegenia M. over and over when the latter was still on the Junior Circuit. Yuzuru constantly loses at SC, because he constantly bombed the SP the last two times he was there. So while politics may play a part, there's only so much that can be done and the rest is up to the skaters.
As for the process you mentioned, I agree it makes sense to explain the issues associated with "junior" skaters. That said, Mirai has not been a "junior" skater in nearly a decade - there's no excuse for her to be skating the way she has without really focusing on the PCS over the past decade. Had she improved on this aspect to her skating, quite frankly, it could have saved her on a couple of occasions over the past few seasons. That's the part that I find so disappointing - she certainly has the ability to sell the program, but seems content to stick with 7s in her PCS in the hopes of rotating (which she is still struggling with).
If Mirai rotates the jumps and others falter, she may make it out of the US and onto the Olympic and World teams -but thats it. As for medals outside of the US, when others can routinely rotate 7 triples and do it with some expression and transitions, there's no way Mirai will be anywhere close to the podium unless others bomb. At this point, Mirai not only continues to struggle with underroations, but she's also dead in the face - not a fierce combination.