To people who actually spar 3 rounds IRL, how exhausted compared to TOTF2 are you?

Obviously getting punched in the face, body, blocking is a definite thing. I've sparred IRL before and found myself exhausted after round 3 but had zero experience. I see some of these fitness youtubers, boxers, so on, breathing/sweating pretty rough after a TOTF2 match so with that in mind.

TLDR: IRL Sparring, say you do three 3-round 2-minute sessions, and the same in TOTF2, how close are these two as a workout?

Asking for science.