Well my point is that, by dry weight, mushrooms are mostly chitin.
If chitin was terrible for human health, Italians would've gone extinct a long time ago.
They want us to eat the bugs, but it isn't because they are trying to poison us with chitin.
Check the quantity of chitin in fungi and insects.
Check whether or not humans evolved the enzyme chitinase, specifically to digest chitin
Read the study again, you still don't get it.