Did you ever watch what Yoshi said about Dawntrail ? They made preview alpha version of some dungeon with statistics of warrior solo tanking dungeon without healer meanwhile Yoshi said whole developer team try to inspire with Elden Ring and how hard is to play it. Also he said few times Dawntrail will be more hard than any expansion before....maybe they dont want to scare people before release and players true experience. Maybe it will be really important to be a healer if Yoshi really said it will be hard....and honestly....i think it will be.