This is disappointing end to me. With a ton of schemes appearing during all season, a ton of hype to Baam, an irregular that now has one the most powerful weapons in the tower, and a ton of friends in danger… Baam and his friends come to get safe by the intervention of a character that barely has anything to do with the plot, and only interested in having his workshop tourney safe? Sorry SIU but I don't buy such a poor plot. ... that scene with all friends landing safe was just absurdly silly. It's like if the author would be afraid to kill some of his too many characters that barely makes something different than being friends of Baam. And with all that hype to the thorn, we only see 2 little blasts of it... The plot had potential; to me the best would have be some revelation of the power of an irregular who was forced to unfold it to face the adversity of everybody (FUG, and The Workshop Organization) trying to capture him... But now we go home with that big ass sit in the chair and doing nothing to resolve the last and most important battle ... Boooo! Very Bad. Sadly ended this way.
Have you missed the multiple mentions in the last ~12 chapters that their only goal is to gather everyone up and escape? They just fought the FUG team to get the guide back, it's been mentioned a few times in the last chapters that baam is low on energy/the team is in a pretty dire situation. I'd liken it to when shanks came and stopped the whitebeard war, the main fights of the arc had already happened.
I honestly don't think your criticism is valid.