Having watched more of the cohn's stream it seems to me that it was never intended by the devs for the player to "lose the game". Comparing it to XCOM2 where the aliens get progressively stronger and if you can't keep up you'll end up losing more and more troops(with equipement) and income(due to losing missons) and end up running out of money to hire new recruits. Then you either lose the base defense mission or the avatar counter fills up and its gg.
Here there is no such arms-race at all because you can always go pick the easier contract. The expenses are very low too, imo they should be increased at least by 200% or so to make the early game somewhat challenging. Also, i didn't notice any increase in expenses as the games goes by, so for late game even that would be dirt cheap. Like the first non-story half-skull contract was 200k c-bills to kill 5 tanks, and the one after the last non-embargoed story mission was two skulls with 700k c-bills to kill one tank and one medium mech, while the expenses are at constant 200k per month. Repairing mechs shot to pieces is pretty cheap too, like replacing a center torso on a medium costs about 80k, which is more than made up for by even the easiest contract.
Well, someone could say that it was impossible to make this game challenging while also letting the player pick contracts at will, but the difficulty levels would have rectified it somewhat imo. Though i guess the devs might have thought something like: hey we design a game that cannon be lost, whats the point of making it even slightly challenging if It would only prolong a "playthrough" and some players might complain that they have to grind.
So, yeah. It looks like without mods it won't be very interesting as "sandbox" type of game, and would warrant a only a single playthrough to see the story(at least for me).