This is not an islanding problem. The vast majority of wind turbines and every solar PV inverter can provide reactive power. They are mandated to provide this

This is not an islanding problem. The vast majority of wind turbines and every solar PV inverter can provide reactive power. They are mandated to provide this in many parts of the US and Australia. Frequency and reactive power are not directly connected. Active power influences frequency, reactive power affects voltage. Reactive power does not change whether a renewable generator is a load or a generator. Low-voltage ride through, including reactive power requirements have been in place for over a decade now, at least in Europe. The comment above demonstrates a shocking level of misunderstanding.