I have a couple points to make as I see multiple errors in what you've posted:
Alina was weaker last season because her body went through changes with puberty. All skaters go through this. Liza had a huge decline for a few years and even a technical master like Mishin couldn't bring her back to 2015 form until very recently. With Alina, we can see with test skates and Japan Open that her jumps are better than they were last season, showing that they are working to adapt her technique to her new body. At IDF, she had a sub-par performance. But this is just one competition out of 3 performances so far this season. If you're comparing to her most successful Olympic season, it also wasn't perfect; she had a bad time at IDF scoring as low as 62 in the short after multiple major errors including falls and URs. You can only say it's a worse season than her olympic season after actually seeing the results of the season. But Alina being in worse shape doesn't mean Eteri isn't helping her.
Eteri never simplified Evgenia's content in the Olympic season. In fact, the layout that Evgenia performed at the Olympic season had a BV that was the highest in her international career. She just lost to Alina who was stronger technically. Alina is now losing to others who are stronger technically. Eteri can't magically inject quads and 3As into her students; the 3A are just better jumpers currently, not because they're younger. Alina couldn't do quads and 3As at 15, and Evgenia couldn't do Alina's olympic layout at 15. They didn't have these jumps and then lost them due to growing, they never had them at all. They're different skaters with different limitations in their athleticism and this doesn't have anything to do with age or tossing older skaters aside; Eteri works with the talent she has and is not a magician.
The bolded statement not only applies to Eteri's older skaters, but to all Russian ladies. They are already buried by the 3As because they simply cannot match their difficulty. Alina, Evgenia, Liza, Stasya. Coached by Eteri, Brian, Mishin, and Chebotareva. Go back a few seasons and you'll see that Radionova, Pogorilaya, Tsurskaya, Gubanova were all buried by Alina and Evgenia's technical prowess at the time, and they all have different coaches as well.