In the past, I have seen similar schemes questioned on grounds of:

- tethering, they likely need to be anchored in shallow water (<100m) to reduce expensive anchoring gear and potential entanglement,

- high wave states, what will happens to the booms and collected plastic during storms? Particularly in shallow waters where waves rear up.

I imagine testing in the Pacific would address the first, and in the North Sea for the second. But testing in Dutch lakes may not help assess either. I don't question the need for such a solution tho, hopes it works.