1) Alina had UR almost the entire season, even though some of the jumps weren't called at competitions. She won the WC with clean programs but it doesn't mean that she didn't struggle this season.
2) That's also not entirely true. If you follow her appearances from after the Olympics until today - you would see a difference.
1) Her main problems with ur was with her Lutz-Loop. And the inherent problem with the Lutz Loop itself is that its difficult not to underrotate it. Take Mao Asada for one, who did -Lo combinations back then and she also got urs with it. The other jumps she's been fairly consistent with, save for the few 'disaster' skates she had this season. I say disaster figuratively because she still managed to do pretty well in general. So. The team has been working on the jumps and from the start of the season till now, her jumps have gotten a lot better height and rotation in general. I say look at the 3S for one, and of course the Lutz Loop/Toe in general also has a lot better height.
2) Evgenia at the start of the season maybe, she was slightly heavier then. But at this point in time? She did an ice show yesterday where she wore her old Anna Karenina costume, and she looks more or less the same as she did last year. The large difference in style of costumes also play a large part in her possibly looking different.
If you look at Alina, she's not really the thin skinny small skater type. If you did a sbs comparison of Alina and Tukt's thighs, they're basically about the same circumference. Other than height tbh from last season to this season her body hasn't changed that much. She's lean and muscular, built more like Michelle Kwan than Julia. She also has a much more sustainable technique than Julia did.
Julia at 16 vs Alina at 16 were at very different stages of growth; Julia was pretty child-like when she won the olympics but Alina look pretty matured by the time she was at Olympics. Say all you want but you really can't say she has a 'child's body'. She's obviously not done growing completely, but she's more or less there. I would hardly say her puberty was 'suppressed' or any of that nonsense.
As for Evgenia, to say its puberty that caused her jumps to change would be fairly erroneous. Like. She's 19? almost 20. If you see her body since 2015 has changed gradually and she's adapted pretty well. She landed jumps with like 98% success rate in competition; there are few skaters who can lay claim to such consistency. The only time she's faltered was at the start of this season? And that was because 1. Injury that basically happens with every skater in the sport and 2. Coach change and technique changes that she needed time getting used to.