@WandererUber No.
The grid is fragile because the grid is fragile.
We w0nT knOw Th3 caUsE foR m4Ny d4yS !!
Your thesis depends on the idea that there are no constraints or restrictions places on Spanish grid engineers (and other engineering types) by EU politicians.
The immediate "cause" of the failure isn't the issue. The inability to recover is the issue.