
Jason and Ilia are at completely different stages of their lives and careers.
Jason has 158k followers on Instagram, which is a completely different order of magnitude from quadg0d's ~6600 followers.
Jason's post from today about GPF news already has ~6800 likes.
I don't try to keep up with Ilia's multiple Instagram accounts -- but he does/did(?) have a separate one devoted to off-ice stuff; yet another one devoted to gaming; and perhaps even others devoted to I don't know what.
As for his skating account, I get the sense that young Ilia likes to show his real-life social circle what he is working on/attempting. From my very sporadic/casual/non-scientific scanning of comments on his quadg0d posts, a lot of them appear to be reactions (sometimes teasing) from friends whom Ilia knows. And he often replies back (sometimes also with teasing).
IOW, I think Ilia's social media still is very much about being "social"/sociable with peers.
(At the same time that he is a smart kid who would be aware that skating journalists/bloggers/fans have started following him too.)
Meanwhile, I would say that Jason's social media is far more about offering a connection to his large fanbase -- with journalists/bloggers looking on. And far less about interacting with peers.