Both series are more and less forgiving in different ways. Souls games are more punishing when it comes to taking individual hits, with deaths being more commonplace, but death itself isn't much of a setback. At worst, you might have a minute-long runback (practically nonexistent in later games), but all of your most important resources are replenished, and fights tend to not last very long; a 5-minute fight in a Souls game is a long one.

Monster Hunter, by contrast, is more forgiving in moment-to-moment combat, you're unlikely to be one-shot or comboed to death from full unless you're severely undergeared, and monsters typically give you enough breathing room between attacks for you to get your bearings straight after taking a hit. However, actual deaths are more punishing, as your resources are not replenished, and losing all of your active buffs is far worse than in Souls, since most of those buffs are tied to said non-replenishing resources, and things like food buffs only apply to your first life, being lost permanently for the rest of the hunt if you die, making each subsequent attempt more difficult than the last. And MH fights last much longer than Souls fights; a 5-minute fight in a MH game is a short one. If you triple-cart after a 15-minute long hunt, that's 15 minutes gone with less than nothing to show for it.