I'm not sure how you can package solar cells, hardened RX/TX hardware into a cubesat that only weighs 1.33 kilograms.
You would need onboard:
A battery, charged at the start to supply enough power to unfold the solar panel, and powerful enough to make sure the thing operates at night (around 40 minutes of its orbit).
solar panels mounted to a deployment mechanism.
cooling to cool the battery and TX hardware
radio antennae - probably deployable (more mechanisms) and dedicated RX/TX
RX amplifier and A/D convertor
Routing firmware on hardened logic board (to transmit/receive properly from other birds in the network)
TX amplifier and D/A convertor
and it'd be really swell to have just a tiny bit of propulsion on board, because we can't afford to put a huge amount of litter into LEO. Manmade Kessler Syndrome, no thanks.
I'm not sure you can pull something useful off with that weight restriction.
Next, you need a frequency band you can soak with your signal. A shared downlink channel may work (may even be necessary) but requires a lot of synchronization between the satellites, which is less than trivial, especially given the speed they're moving at relative to one another and the ground. I'm suspecting that a priori the Doppler effect is going to make a global network not feasible.
Second, RX/TX strength. Who controls the content? In order to make this feasible in any way, you want small RX on the bird, compensated by big ground TX. Due to the relatively low orbit compared to TV birds, which are often up near GEO for economic reasons, TX doesn't need to be as big as a TV bird, or ground RX can be scaled down.
Realistically, can we expect even 100W of TX power, given the size/weight constraints? I very much doubt it. Let's assume they launch 50.000 cubes (if their budget is right, that means they spend about half on launches)
The earth has 510 km² of surface are. Each cube has to cover, in the best case, around 10.000m² of surface. That makes for a signal level of around .01 W/m² (assuming a perfect antenna geometry and a magic constellation), which is meaningless without knowing the transmission frequency, which in turn determines the available bit rate.
A low bitrate broadcast isn't very useful.
So while this may make it back-of-the-envelope workable (the signal strength is almost achievable, and with the right frequency, there won't be a need for too big a ground RX antenna), realistically, there's little gain in wasting money spewing trash into LEO, and face Doppler, when we could use terrestrial signalling which isn't much more expensive, but much less cool, and people would actually have to perform maintenance, instead of just putting more trash into LEO.