Space based solar might not take a form where we just put mirrors in space to boost the output of existing terrestrial solar cells. The benefit is that the receivers on the ground can receive energy directly from the sun when the sun is up, and the space mirrors can be used to provide light to areas that are completely dark in winter.
I don’t think microwave beaming is ever viable
Most fusion concepts are thermal power plants. Those have inherent downsides that have nothing to do with the nuclear energy providing the heat for the steam turbines. So they will never fully replace renewables. Helion’s concept might work. But that remains to be seen.
The station couldn't be used as a threat. And its use would be very limited in time.
Taking out the rogue orbital power station would be a competition between very trigger happy militaries. Who wouldn't want to demonstrate their satellite killers on a legitimate target?
Stuff in space is very vulnerable due to the high cost of shielding. How would an energy weapon in space fare against its hardened counterparts on the ground? How would it defend against clouds of shrapnel?
High ground is beneficial because you have direct line of fire where the enemy hasn't. But there is no ground to hide behind in orbit.
So what about this orbiting duck of yours, the power station recently turned rogue?
Look, the satellites you share an orbit with are adjusting their trajectories to intercept yours. Undisturbed, they will pose collision hazards within the next days. You must fry them all before they complete the adjustments. Do you have a real time feed of their position for targeting? Bet you do, you're a supervillain after all.
But some satellites are passing behind earth, they will complete their manouvers before they emerge from earth's shadow. The first hit is predicted in just 130 hours.
But hey a bunch of missiles took off on the other side of earth, they are now on a ballistic trajectory that intercepts your station's orbit. Thanks to your flawless targeting, you manage to melt some of them. Their debris will hit anyway, your station has 19 minutes left before impact.
Meanwhile, some subs poke laser scopes out of the sea, taking shots at your station. You divert your energy from the incoming missiles, but when you try to hit one, the scope is submerged again. You produce a plume of steam.
And what is this? What was supposedly a radar array starts to beam microwaves your way. Your station overheats in seconds because it has almost no mass and lots of surface. You could've taken out maybe one of the hundreds of antennas in the array if your comms hadn't already been crippled by a laser.
As you lift your gaze from the now useless controls, the sky is lit by a tactical nuke that was hiding in a spy satellite. It happened to be close enough for a crippling EMP blow.
I don’t think microwave beaming is ever viable
Most fusion concepts are thermal power plants. Those have inherent downsides that have nothing to do with the nuclear energy providing the heat for the steam turbines. So they will never fully replace renewables. Helion’s concept might work. But that remains to be seen.