I know it would and I'm n ot so sure they would have even thought about that!!!!
I remember when the "egeria" first started moving into Delta marinas and making difficult to get in and out of the slip, some owners tried floating black plastic to block the sun, hoping the stuff would die off. It did not. That weed looks like the long skinny stuff put into small home aquariums.
Dept of Boating & Waterways has finally found something which kills most of it without harming the native flora and fauna.