For what it's worth, scaling the freestanding Mt. Kilimanjaro volcano is about as intense as a 4 day backpacking trip up up up to high altitude, little to no watch-risky technical climbing required for the common routes.
I've personally struggled like hell on the top, almost hallucinated and so did rest of my team members. But we made a junior mistake of going too fast up on summit day. When I did ie Mont Damavand in Iran, which is just 250m lower after cca 3 years, no issues and roud trip was just 2 days. But I've trained and did some crazy stuff in between. Most folks don't do that kind of stuff.