The grid is not just an aggregation of individual sources and sinks; it takes active effort to keep them all working together in a useful way without just collapsing again into another cascading failure. For that reason, your solar inverter doesn't come on until the grid operator wants the solar inverters to come on in your section of the grid.
It's tempting to think of the grid as something grid operators control, feeding power from point A to point B, but the grid is actually largely uncontrolled - the power just flows wherever it wants to - and the only controls they have are turning on and off generators, adjusting their throttle, disconnecting loads (rolling blackouts) and sometimes opening circuit breakers (though this is not normally useful). They don't even have precise real-time monitoring of the whole grid - only specific measurements in specific locations, from which the rest is estimated using lots of maths (which is how you would design it too, if measurement devices cost $100,000 apiece). That's why it's not a trivial task to keep it working.
However, you're able to have your own, private miniature grid, on which you can power your own loads from your own generators. It's even possible to do this with solar inverters! You will need to specifically seek out this capability, and get extra hardware installed, which is probably why you don't have it. You need a "transfer switch" to definitively disconnect your private grid from the main grid when you're using your private grid capability - it's not allowed (and not safe, and will blow up your equipment anyway if you force it) to just feed power onto your local unpowered section of the grid.
Solar inverters could simulate inertia by not running at 100% most of the time, but you do want the free energy machines to run at 100% as much as they physically can, because it's free energy, which means there's no buffer for simulating inertia. It's been commented many times that batteries can be used to simulate inertia. You can also literally just add inertia, in heavy spinning lumps of metal that don't do anything.
It's tempting to think of the grid as something grid operators control, feeding power from point A to point B, but the grid is actually largely uncontrolled - the power just flows wherever it wants to - and the only controls they have are turning on and off generators, adjusting their throttle, disconnecting loads (rolling blackouts) and sometimes opening circuit breakers (though this is not normally useful). They don't even have precise real-time monitoring of the whole grid - only specific measurements in specific locations, from which the rest is estimated using lots of maths (which is how you would design it too, if measurement devices cost $100,000 apiece). That's why it's not a trivial task to keep it working.
However, you're able to have your own, private miniature grid, on which you can power your own loads from your own generators. It's even possible to do this with solar inverters! You will need to specifically seek out this capability, and get extra hardware installed, which is probably why you don't have it. You need a "transfer switch" to definitively disconnect your private grid from the main grid when you're using your private grid capability - it's not allowed (and not safe, and will blow up your equipment anyway if you force it) to just feed power onto your local unpowered section of the grid.