An important perspective.
I would add one further observation.
The greatest challenge is often not coordinating shared resources, but ensuring that organizational priorities are reflected in actual capacity allocation.
Declaring a project as high priority creates little value if competing commitments remain unchanged.
Proactive project management certainly helps make constraints visible early, but lasting delivery performance depends on timely organizational decisions that align priorities, capacity and accountability.
In that sense, preventing last-minute firefighting is less about working harder and more about preserving coherence between strategic intent and execution.