I don't understand what this means. If you mean Facebook-- Facebook didn't drop billions of dollars in to free space optical comms.
> GEO to LEO is not LEO to LEO
Yes, GEO-to-LEO is worse in every way (assuming the LEO satellites are in the same inclination and have the approximate same orbital period):
* Longer link distances. (More path loss, worse link budgets)
* Higher peak angular rates for pointing.
LEO-to-Earth is mostly worse:
* Shorter link path, but atmospheric dispersion (More path loss, worse link budgets, plus things like multipath).
* Higher peak angular rates for pointing.
* Less demanding pointing precision due to shorter path, though.
The hard part isn't the optical comms in space. The hard part is fitting multiple precision-pointed transceivers into a tiny volume and mass budget.
Given that there's systems that have successfully flown doing links from GEO to LEO (e.g. high angular rates again), using several year old conservative technology, it's not so bad.
There's a million little details, of course. Just conduction cooling for fast optical transceivers is going to be annoying in space, for instance.