The performance of version 7 is much worse than version 6

[j-xzy]

Describe the bug
setValue will trigger much Subject.next in useController and useWatch.

v7:

v6.15.4:

Codesandbox link (Required)
6.15.5: https://codesandbox.io/s/empty-darkness-muuch?file=/src/App.js
7.8.8 https://codesandbox.io/s/epic-leavitt-pq4ux

[bluebill1049]

can i have a v6 version of this? happy to investigate for a better perf solution.

[j-xzy]

6.15.5: https://codesandbox.io/s/empty-darkness-muuch?file=/src/App.js
7.8.8 https://codesandbox.io/s/epic-leavitt-pq4ux

maybe too many observers cause performance degradation