Yes, you are absolutely right. If you have an actively leaking site, fixing/patching it might send you into the high pressure (intracranial hypertension) hell until another leak appears, or until your body somehow adapts to it (by decreasing production of CSF - I know that’s possible because people produce less CSF as they age; or by getting used to it).
Now, “much” lower or “a bit lower” is a good question. Because there are theories supporting cyclic reinforcement and “equilibrium” idea (Dr Fargen), basically saying that if you have a slight hypertension, it might cause the brain to swell, causing the venous sinuses to shrink and allow less blood (and CSF) to flow out of the limited volume and not flexible (expandable) skull (you can watch the YouTube video on CSF production I posted into my YouTube Favourites thread), causing even higher pressure of CSF as it gets accumulated and not effectively drained, causing even more pressure inside the ventricles and more brain swelling, leading to more restrictions on venous sinuses etc, until the pressure in the venous system can’t go any further (as the fresh blood is constantly pumped in) and some equilibrium is reached. The result is you have high venous pressure inside of the skull, narrow(ed) venous sinuses, and high CSF pressure.