I don't quite understand the narrative about underwhelming first season in Liiga. 99% of players don't have any business playing there at age of 16(he turned 17 halfway of the season). I think Barkov has been the most effective player at that age and he scored 16pts in less games and also 4pts at WJC (like Lambert). Tappara was much better team that year than JYP last year and Barkov is a perfect match to Tappara's/Dufva's hockey. While last season must have been tough to every player in JYP (Coach drama, some player(some owners) drama, financial struggles, Covid- year etc.).
I think under the circumstances he did pretty well as he is not as physically ready to play against men like Barkov was. This year should be the one where he really should make his mark in Liiga. I think most recent high picks from Finland started to look good in men's league during the draft year (Kakko, Laine, Puljujärvi, Aho, Barkov) so I wouldnt worry about Lambert either. I think he should be in top3 overall conversation when the draft day comes.