We're talking about lower leagues here, so the comparison isn't really applicable. However, the theory still applies. Sure, we're in a bit of a purple patch with the academy coming through, but think how much it has cost the club to upgrade the facilities, employ the best academy staff, pay the wages for the players (they're not on peanuts, let's remember, Kane was on £10k a week before this season), pay for transport fees for tournaments internationally. It soon adds up and if the club fails to make a player capable of pushing for a space in a team that's ultimately aiming for top four, it just isn't worth it compared to signing a ready made option from France etc.
For the lower league teams who don't have the money the TV deal provides, how do they justify that sort of outlay hoping a player from within their catchment area (which is often shared by a PL club, who hoover the top talent) will be good enough to play for them, let alone several players to fill a squad. By forcing them to field an 'x' amount of homegrown players, you'll just be furthering the gap between the top league and those below it. It's a nice idea but doesn't really work, there needs to be a greater share of the TV deal that filters down the competitions, however we all know every PL club will be fighting tooth and nail to get as much of those billions of pounds as they can.