We know that when it happened, Spain was exporting gigawatts of energy to the rest of Europe. The issue, therefore, was not "not enough electricity," which makes the blackout harder to grasp (at least for me). But since the grid needs to be balanced, even too much power can cause trouble.

I do agree with you that the lack of information we have on the matter is alarming and suspicious. Our grid is running at the limits of its capacity and is very fragile, and the instability of wind and solar sources is definitely not making things better