Idk what 'Warlords' is, but assuming it's some technoverse where technology has bizarrely only improved in one or two fields and those only in being able to present what is capable today more readily plus some weapons technology..actually.. not assuming that, coz it could have any number of odd precepts =)
Mining where?
Machines can be built to operate under constant environmental constraints that people just won't (normally) put up with(that is to say, they will want to get out of those suits) which means you need a living environment, habitat for them, vacations if nothing else.
The only real reason to use people for anything in the long term, is because people will(want) to do it, not because it's 'cheaper.'
Fact is that even today a significant proportion of human industry is redundant (99% of advertising spending is spent trying to attract consumers to one particular variation on a product or service of many that can do that job, for example)
At some point, hopefully long before a century and a half has passed, the general comprehension of 'economy' will reorient to "those mechanisms of exchange whereby things that need doing get done" as opposed to "i have to justify my existence to society so i must convince it it needs something doing" at which point...
Pretty much any argument other than habitation provision, workforce replenishment, mission duration, transport costs & h&s can quite readily be answered with 'whatever a robot can do, a human with robotic support can do also.'
But tele-operation is a thing, and realistically it's much easier to build a single partial rig and a transmitter than it is to maintain conditions suitable for people on-site.
What you said about 'nothing too crazy.' 150 years ago radio communication did not exist, farming was manual labor, modifying the human form was all about surgery and breeding programs, in 25 mankind will be able to reliably synthesise biogenesis...
Question is really, in 150 years will humanities loftiest ambition to be to sit in a tele-op rig? Or to alter itself so that it can do those things it's products would otherwise do better.