This kid is really flying under the radar.
Yep. He basically lost his spot in Jokerit juniors as he was considered too small at the age of 15. Moved to rival HIFK juniors and gained enormous amount of height. This caused back problems and he missed almost completely season 14-15. Gaining ridiculous amount of height makes you lose your coordination for a while and when we add the back problems, it's natural that he wasn't seen in junior national teams.
Also the Finnish U20 league doesn't get that much attention as the most talented juniors are already playing in Finnish elite league with men. There are few gems though and usually these guys are heading to Northern America leagues that don't allow players with pro background.