Yeah I think they just meant the turn of phrase to be: “worse still” or “and on top of that”.

PS:

I’m still not making sense probably.

I think they meant it like

Disorder is bad but the combination of disorder PLUS people chirping is even worse.

E.g., it’s bad enough I smashed my foot dropping a brick on it but on top of that I stubbed my toe, too.

Smashing my food is bad but even worse is [also] subbing my toe [on top of the already smashed foot]