My 3kW solarinverter (manufacturer SolarEdge) installed 2 years ago supports this out of the box. It must be activated in the setting tho, so probably not every installer cares about this. Thuis does come at a small cost in solar generation (maybe a few percent, way less than the yearly variation)
Comments
Its (a little) more cost.
And it's not obligatory, enforced by law.
And it's not a coordinated response, so it still can become an oscillating force.
I can't speak for other regions but in the EU this is handled.
The main point of in practise, it isn't binding or controlled that it's turned on.
(suspect on less kwh production)
And systems are already there for atleast next 20 years.