I'm not sure how a single inverter failure could drive voltage high. Or how a varistor failure could cause a problem... The inverter has to perform a DC-AC conv

I'm not sure how a single inverter failure could drive voltage high. Or how a varistor failure could cause a problem... The inverter has to perform a DC-AC conversion and has many more ways to fail safe than unsafe but I'm not saying it is impossible. I've seen some oddball things. But it certainly isn't a widespread issue. Smart meters report voltage, the utilities would know if this was happening and given how much they hate rooftop solar they'd be yelling about it if they could.