Confused about how many calories cardio really burns - Is it less than I think?

I keep hearing mixed things about cardio and calorie burn. Some say even intense sessions only burn around 100 calories, while others say it can be up to 400+. I recently did an hour of mixed activity — mostly walking with several 2–3 min moderate jogs and one near-vigorous interval — and now I’m unsure how much I actually burned.

I’ve also heard that the body adapts and NEAT decreases, so you end up burning less over time anyway. Is walking better for fat loss in the long run because of that?

I’m not trying to overestimate what I burn — I just want a realistic, science-based understanding without fear or obsession. Anyone have insight or experience with this?