I'd wager Khelif wasn't that skilled a boxer. Possibly even lazy if they just didn't have to try that hard. Potentially a highly skilled female boxer could out maneuver a shit male one providing they can keep out of arms reach.
Since 2019 Khelif has started winning things & now they are at the Olympics so you might assume their skills have been tightened up.
Two female boxers have BOTH said they've never been hit 'like that' before, and these are women who get punched for fun, for sport! They are pretty damn good judges of what it feels like to get punched by another woman. I hope, for them, that they've never been punched by a man (or a DSD body that's been through male puberty but was assigned female a birth. The only time that phrase counts) so this would have been a serious shock - and it was.
Make of that what you will.