i already countered that argument, but to spell it out: sun synchronous orbits which see the sun all the time are a 1d manifold (approximately) and quite busy already, so they won't come to the rescue.
My point is that SSO isn't "coming to the rescue", it's literally the entire premise of the idea (greater availability of solar power there vs anywhere on earth). I don't buy "there's no more room" as an argument when we're talking about space, even in a relatively crowded set of orbits like SSO.