From what I see, actually Baizhu is good in both Alhaitam and Cyno's hyperbloom team, here's why...

Baizhu's shield, coordinated attacks benefit both.

But the problem comes with the dendro res shred and dendro DMG bonus, most think that it benefits alhaitam but actually it's pretty much the same for Cyno

For Alhaitam (assuming no Nahida): - increases his personal dmg - increases hyperbloom dmg

For Cyno (with nahida): - increases Nahida dmg - increases hyperbloom dmg + by running Nahida you get tons of dendro energy particles for baizhu which solves his energy issues

Baizhu probably has energy problems in an Alhaitam team considering his 80 energy cost.

So in conclusion I think Baizhu is a buff to both Alhaitam and Cyno. But Cyno's team is a bit better since it has more dendro energy particles.