Maybe a dumb question, but why? I don't like that it exists, but isn't it self-contained? The main reason for cleaning it up seems to be quoted as [1], which oversimplfies to 'animals might eat plastic, and it affects them', and it will make microplastics. But these problems seem to be localized to the garbage patch. I could see it as a asbestos situation where its only problematic if you disturb it. Ongoing dumping seems to be a bigger problem as it's not localized.
[1] - https://microplastics.springeropen.com/articles/10.1186/s435...