I think Forbes uses a measure called 'Enterprise Value', which is simply market capitalisation plus net debt. It's a measure of how the business is funded but the weakness is that it doesn't separate leveraged debt, which doesn't produce a return on investment, from debt taken on to finance things that should generate a return, such as plant & machinery, property, other companies you buy, etc.
If you make widgets and your production is close to capacity, meaning you're turning orders away, or are in danger of having to do that, it probably makes sense to buy another widget-making machine or set up a new plant altogether. You'll probably borrow money to do that but if you've done your sums right it'll produce additional revenue that'll at least cover the cost.
Debt like the Glazer's loaded onto united, which is a dead-weight and costs them money, doesn't itself produce a return. It does for the Glazers but not for united. It hasn't been invested in the team or any other revenue-generating asset. But using EV means that their debt increases their value. It doesn't make sense.