That really is tricky, kind of defining a point where too much is gone for it to be worthwhile, and hoping it never gets there….
But really yes the crowding/price raising combination as it exists now (and will exist if prices get raised) simply isn’t sustainable in terms of morale of the visiting guest, the Cast Member, and having time to properly maintain things without it causing people to be angry at closures or loss of things/unpleasant conditions while visiting.
They’re digging quite a hole for themselves - I don’t think it is the park’s grave, just yet, to be somewhat hyperbolic - but with continuation of the worst confluence of possible factors in years ahead, it could be, as sad as that is. The shelf life for Disneyland isn’t ‘eternal’ in the end - could be the factors above and just too expensive and crowded that it bleeds out, or a big natural disaster (great old ones forbid) and too much damage so that rebuilding just not practical. I hope, truly, things get better somehow even if tough decisions have to be made.