exactly. would veritasium, 3brown1blue, action lab, nile blue/red, up and atom, simone, etc. even exist via the PBS funding model?

The "PBS spacetime" channel exists, so they're doing something right.

If it was properly funded? Quite possibly. If it had the same funding as Youtube's ad revenue then I think you'd have all those, but maybe a lot less of PewPewDie and Dude Perfect.

which channel is simone? the name is too generic, a search only turns up uninteresting stuff.

Pretty good chance they meant Simone Giertz, who is fantastic:

https://www.youtube.com/channel/UC3KEoMzNz8eYnwBC34RaKCQ

She got her start by being "Shitty robot queen" on reddit, not youtube.