And in regards to needing two different triples - did you see the senior protocols from worlds? Now seriously, how many pairs actually landed two different triples? A lot of pairs are still using one triple (either on its own or in combination with double) and double axel (one or two in sequence), or triple-double-double and double axel. The jumps are important, but so are all other pairs elements. Having only jumps is not enough, whereas having average jumps (one triple and double axel) in combination with great pairs elements can put you in the 5-10 place at senior worlds.
Russia is not interested in pairs who can place 5-10 at senior Worlds. They want pairs who have the technical ability to take over from V/T and fight for World and Olympic gold medals. None of the Russian juniors have shown they have that potential, except perhaps Gainetdinova and Tarasova/Morozov. The other Russian juniors could become another Bazarova/Larionov at best.
In comparison - the other Russian junior teams (the ones who according to you have no potential):
Lina Fedorova / Maxim Miroshkin: 2nd and 1st at JGP, 1st at JGPF, 3rd at junior worlds
Evgania Tarasova / Vladimir Morozov: 5th at JGP, 5th at junior worlds
Vasilisa Davankova / Andrei Deputat: 2nd and 3rd at JGP, 2nd at JGPF
Maria Vygalova / Egor Zakroev: 3rd and 2nd at JGP, 3rd at JGPF
Gainetdinova doesn't compete on her own but in a pair. G/B weren't a strong enough partnership but with another partner, she could have much better results.
Note that despite G/B's weak twist, G/B easily beat V/Z and T/M in the long program at Russian nationals and they came very close to F/M's long program score. If Gainetdinova skates as well as she did at Russian nationals in the long and has a taller partner with whom she can make up the lost ground on the pair elements, do you seriously think the judges will give the title to a pair like F/M?
She could present the "whole package" if she skates to her ability. The other Russian juniors, except T/M, cannot even if they skate to the best of their ability. So in a "everyone skates their best" scenario, the battle will be between her and T/M.