Sorry but I have to completely disagree with most of what has been written here. It's obvious that this comes from huge difference in mentality. What I see in the west is that there everybody cares for and only for the winners and try to see everything as a struggle between some two sides, but this is just not how things work in slavic countries. Let for a while try to see this NOT by what you want to see but with understanding why things are that way. The hard thing is that there is very little comparison as there are very few such impressive competeing athletes training under the same coach. But let me try to explain at least some basics:
1. Here in the central and eastern Europe there is very strong feeling that kids (or teenagers at least till they are 18) should never be treated as superstars (even if they are like Alina

). Whether or not is this right feeling, we feel this could spoil them or they could get used to it too much and stop trying to do harder or could expect too much celebrating for their achievements.
2. Alina's personality. As everyody here understand, at least I think, she is not the type who would desire for too much attention by public. She does not avoid it when it is necessary and she deals with it well (you can see her answers are very well thought-out and pretty mature for her age), but I feel she takes it as a necessary evil. Evgenia is taken as more adult, more experienced with public and media pressure so it is not considered as so much dangerous when she is more the topic of media attention.
3. Coaches attention. Alina herself admitted she is the type who has to be pressed for better results. Starting to celebrate her too much could damage her attention to training. And in fact there not such a big difference between Eteri's attitude towards Zhenya and Alina, in the documentaries you can see Eteri could be pretty demanding with her too. Again, she is part of her team just longer so she has more experience how to fulfill Eteris demands and how to get along with her.
4. We are not accustomed to change attention quickly. I see people in the west have no problem to become suddenly enthusiastic with completely new persons and things (and loosing it for old ones too

). We don't feel it that way. Changing attention, preferences and so on takes time for us. That does not mean we are not enthusiastic too for new people but we mostly try to share it between the things or people we know for long time and the new ones.
So those are my basic feelings about what I see. It comes of course from my menthality or life experience and could be subjective but being Slav myself I do not see those things that were discussed here as something surprising or incomprehensible. Just please even if you do not see those things this way, just keep in mund that there arepeople who see some things different way and that does not mean they are not grateful or they can't praise Alina's achievments.