I do think that on the whole, ice dancers are unnecessarily thin for what they're doing.
Some of them are just more of the skinny/slim type. Based on what you see, I don't think Gabriella or Meryl are starving themselves at all, that's how they are. Some people have a faster metabolism.
Now, Tanith did have eating disorders. She said that her coach told her to eat and put on muscle if she wanted to skate better - with more flow - and she saw how much it was working. Isabelle Delobel stated how much issues there are in figure skating about eating disorder too and that it's too overlooked.
This year, one of the change I saw was Stepanova. While still being one of the thinnest out there, she has clearly been training for the Olympics, she has much more muscles than before. And that is helping her skating big time compared to the previous years.
Look at Tessa or Maddie Hubbell - they are not the "common" skinny type, yet easily 2 of the best ice dancers out there.
But I agree that some of them, even if they don't look slim (since they have a lot of muscles), might be putting less in their plates than what they need to be healthy. The danger of an "artistic" sport. I'm guessing there is the exact same things in ballroom and gymnastics.
It's not the Ice dancers I'm more worried about though... female pairs skaters really are thin. I'd like to believe some of them are this way, but 100% of them ?
EDIT : to continue on the weight "issue", Maddie Chock for me this year has lot so much compared to 2 years ago. Didn't she say she started being
vegan ? Now, when I'm looking at Meghan Duhamel (and what she shows us on social medias), I see that sport and a vegan diet are compatible for sure. But if it's brand new and you have to adapt I'm guessing your body changes, and I was surprised to say the least.