I’d say it’s a case of convergent evolution rather than inspiration, especially as the old games didn’t officially support or design around ironman mode. But I think that Massive Chalice did take a lot of inspiration from various roguelikes and apply it to the X-Com template, by doing things like reducing the campaign playtime, reducing reliance on set-piece missions, more emphasis on random events, limiting characters’ lifespan, etc., as well as of course explicitly designing for ironman mode.
Also, the discussion on metaprogression in the Below thread is germane to this discussion.
I’d agree with the general sentiment there, against systems where the player gets steadily stronger by accumulating resources that persist through deaths, before they can eventually win. That just turns into dull grinding, and it was my chief gripe with Rogue Legacy, though there have been plenty of other less egregious offenders. On the other hand, I’m all in favor of metaprogression systems that are about unlocking variety and complexity rather than raw power, like Into the Breach.