At Hot Chips, SK Hynix confirmed hybrid bonding won't hit HBM4E. It's pushed to HBM5 (~2029-30).
Not because the tech failed, it's proven since 2010 in image sensors. It's because bonding 16+ memory layers in a row is far harder than bonding one, and a JEDEC height rule just bought more time for the old method.
More details here in my article: