Neither of these articles says Germany's electricity supply is unreliable. There's no mention of power outages, or equipment damage, or anything like the power crisis in Texas power.
Instead, your citations say renewables are producing more energy than can be used.
That's a good problem. It can be solved by turning some of the supply off, or adding long-distance transmission to move the excess power to where it's needed.
But there's no hint of renewables causing instability or unreliability or power outages.
