Batteries maybe. Allowing "dirtier" non-50Hz power would make things worse, power plant turbines are optimized for 50Hz, different frequencies get inefficient q

Batteries maybe. Allowing "dirtier" non-50Hz power would make things worse, power plant turbines are optimized for 50Hz, different frequencies get inefficient quite fast. So your generation will shrink the lower you go. At the same time generators running at different frequencies will work against each other. At the same time machines will pull the frequency down even further, landing you in a vicious circle that forces the frequency toward 0Hz. No choice but to cut power before you damage too much of the grid and equipment.