To give mu usual US perspective (because I am half-American now after all).....
.....up until 2014, the NFL had a policy that if a team hadn't sold 85% of tickets for a home game by 72 hours before the kickoff, the game got blacked out on local TV.
The logic was that ticket sales were such an important part of NFL team's revenues, and the product was so much better when the stadia were full, that they didn't want people sitting around at home watching the games if the stadium was half-empty.
The rule eventually got binned, in large part because ticket sales ceased to be quite such an important part of NFL team's revenues and it was financially more important for them to get the best TV deals possible (so exactly the same situation that the Premier League is in today).
But something like it could work for the football league?
If, say, Oxford have sold 6,000 tickets (or whatever % of attendance works for clubs' bottom lines) to home fans by Thursday night, the game is available for purchase to anyone on iFollow. If noone is buying tickets, then the blackout comes into effect.
Would prevent you from selling season passes, because noone would buy them if they didn't know how many games they were going to get to watch*, but otherwise I think it could strike a balance.
(*I say noone, but us overseas iFollow subscribers all get season passes, and then randomly find that games like the Wombles aren't going to be shown because the EFL has somehow sold the game to other overseas broadcasters........but then we're all desperate for an OUFC fix and don't have any other options to get it, so they know they can screw us over without losing our custom!)