Responses
Also it's my theory, but seeing how elves benefits to sekai, they must've fo that to the prev tree. Having the tree make the house that result to sekai to be stunted for a moment and not grow. Also after making another house for sekai and his harem exhaust him but have been one of the reason why the prev tree die over time.
Sooo ig those elves also do that to Yurshil the prev world tree. The plot is good but im against in harem so I'll ignore it as long as I can but if it seems absurd I'll stop ಠ ೧ ಠ