Not sure. On one hand, a huge backlog means they're not meeting their demand. Operations may not be in order. Everything else is the same so sales and everything else is equal so I guess money is just deferred? Also huge backlog encourages competition and if you can't deliver, you're going to lose.
But such a big backlog suggests that they're underpricing. So it may be as simple as increasing price and ramping up your production, even though it would likely mean higher marginal costs.
Overall no one wants a backlog. It's not good business
Okay, now same question except one small change.
There's only one company: the one with the backlog. The other company either went bankrupt or was bought out and consolidated into the first company.
Have you ever heard the phrase ceteris paribus? It means all other things being equal. It's a phrase economists use to discuss things in the ideal, sort of like, "imagine a spherical cow in a vacuum" but for economics.
The point of the exercise is not to suppose what other things could have been different to allow these two hypothetical companies to end up in the described state. The point is to actually freeze everything else, do not allow it to vary, and look at the backlog in isolation. Obviously such a situation would never actually arise. Even if things were trending in that direction, the two companies would very quickly diverge from ceteris paribus.
Obviously having a backlog is better than no backlog because unless you make a new sale tomorrow, you have a problem. You will have idle capital and labor resources. Which company do you think has easier access to credit?
Private equity is very much interested in the margins. That is one of the key differences between private and public companies. Public companies are under pressure to grow at all costs. PE would probably be satisfied to make half the profit and double the margin, especially if it also happens to position the company for a more favorable sale. Would you rather buy a business that's at 5 or 10% margin?
The depth of the backlog also happens to be a pretty decent proxy for how much competition there is the market. A deep backlog means there isn't another firm around to fill that demand. That makes your company look better.
Let's go a little left/up the funnel. Imagine two startups, all things equal, their sales funnel goes wide > qualified > sale. They consistently convert 5% of qualified leads into sales. Do you want to be the company that has zero qualified leads, or $4.5b of qualified leads?