Tbh, Stockport, FCUM and Salford are all different - background, fans, owners, potential etc.
EYG has got it right about Salford, though. They were a decent-enough non-league side who the "Class of 92" (and a wealthy Agent) reckoned they could rocket up the EFL. But despite big investment (at that level), they've found that it's not so easy as it looks, and they're apparently losing a packet.
While they too, like Wrexham(?), may have unrealistic ambitions. For example, I've been to their stadium. It's a standard, new(ish) identikit stadium, in a surprisingly leafy/affluent suburb of Greater Manchester - certainly nothing like the image of Salford Docks! That said, at 6k capacity, imo it's perfectly adequate for their present status, even if it's not exactly where they'd like it to be.
However, that didn't stop them from trying to combine with Sale RFC to buy a 12k stadium a couple of years ago, the idea since abandoned:
https://www.manchestereveningnews.co...witch-25798167
Anyhow, the point for LOI comparisons is that if they get it right, those three clubs have a clear pathway up the pyramid to aim for. The problem there is that unless they can get to the PL (v.unlikely for all three), then it's almost impossible to make money in the Championship, even breaking-even is a huge challenge.
Whereas the LOI equivalent for advancement must be to hope for European football, the problem there being that only 4(?) clubs can achieve it at any one time, with those 4 normally being drawn from the same small group of clubs each year.