I can’t see that happening. While the carnage you envisage might well happen, I think you see the pyramid reorganise itself organically. For every Reading that goes tits up, there’s a Rotherham with money to burn. For every Macclesfield there’s a Stockport. For every Ebbsfleet there’s a King’s Lynn. As you’ve pointed out, these clubs can and have mothballed relatively efficiently.
I think we could see a situation where contracts lapse and people move around again when the time comes. The quality of the competition will likely be lower because the athletes are no longer at or near peak capacity. But the league structure itself will, I think, survive.
Football is inherently greedy and selfish. We’re not suddenly going to start being collegiate and friendly.