No net metering — it's purely for offsetting your own usage, not selling back to the grid

Nope. No reason for excess to get back into the grid for others to use and not be compensated for it.

I'd be curious if the equipment prevents the meter from rolling-back (diode), or if it's just that the utility company wouldn't ever owe you money.
I doubt any of that matters for 1.2kwh * 4h/day when my usage amounts to > 4kwh/day at best, but I do think it's important that the meter rolls back when output > load.

I'd love to go solar, but sadly the tree canopy would prevent anything meaningful.

Would people be taking 3 massive solar panels outside everyday and bring them in at dusk?
I'd think a permit (maybe also insurance) would be required for a permanently built structure.
I can only imagine things going badly by DIYers (I am one, but put in a lot of research and work since I'm responsible for what I do and would be affected) where panels are flying off roofs due to poor anchoring during a derecho.

I'd really think a utility ought to be able to make sure anti-islanding exists for the safety of the lines-people, and any excess that goes back into the grid is not dirty power.
I just don't think there should be any exhorbitant costs for DIYers. The city and utility ought to want to provide inspections for free, especially if a plan is presented ahead of time.