It wouldn't be the most practical orbit for narrow FOV imagery but for polar weather, communications, and monitoring for things like over the pole missile launches they're pretty useful.
The entire globe has about 500 billion square meters. 24 bit uncompressed imagery is thus 1.5TB per global image. With some modest compression, you could get a video stream of that from the Starlink network, although the current design of Starlink would make it hard to have room for an aperture with better than, say, 3 meter resolution.
That said, it would be really difficult and quite likely not at all worth it.
That's a very bold claim with no support provided.
Though the live imagery would now need night vision cameras, as we blocked out all our light with our camera support. But one has to take the good with the bad ;)
I think most accepted approaches to constructing a sphere involve first building a series of structural components to form a stable net - as such we could stop the process when we've got just enough structure in place for stability and not so much that we need night vision cameras buuuut... I typed that before buying a bunch of night vision stock so please disregard the first portion of this paragraph - we would absolutely need night vision cameras from every angle.
So that means most of the south and north part of the earth cannot be covered with such a constellation; they would need to be orbiting satellites, which makes "real time" even harder, because it would require an enormously complex choreography to ensure there's at least one satellite covering each square meter, at all times.
[1] https://physics.stackexchange.com/questions/71582/is-it-poss...