Frankly its amazingly concise in how its written and subverts expectations. It happened NT8 as well but its played a bit differently this time.

Recall OT6, OT7, OT9, OT11 and the frigging intro scene to Index III Ep 1 (vomits). The basic structure of their gags is the following

1. Girls in various states of undress.
2. Touma walks into the room/area with the girls still undressed
3. Brief moment of unease where everyone realizes the situation while getting a shot of their body.
4. Touma gets punished by getting bitten/beaten up.

The above structure sucks because the punchline of the gag is focused on the fanservice moment and the guy getting beaten up.

Fast-forward to NT and these redundant type gags have all but disappeared or have had their characteristics greatly changed.

NT4, the same type of gag is implied to have happened with Touma and Saflee Opendays but the actual event is skipped entirely.
NT7, Kamijou is immediately thrusted into a similar scenario by Tsuchimikado's machinations but it works because the punchline isn't focused on the fanservice or the guy getting hurt but crazier encompassing scenario that Touma's been dropped in the School Garden aka no-go zone for males.
NT8, was basically brushing against the gag by pushing Touma and the girls into swimsuit shop but cleverly subverted by Touma thwarting Lessar's plan. The punchline was instead something of anti-joke with there being no fanservice moment but Touma still losing face (this time in a non-physical way).

GT1 also plays out different. post-NT Touma is more trope savvy than early-OT Touma and knows the signs where the gag is being set up so deliberately takes action to side step it altogether. But the world is one step ahead of Kamijou and he runs right into it.

This time the joke works compared to early OT because the order of the gag is completely jumbled.

Touma blacks out and wakes up after the gag has occurred.
Mikoto is giving him his physical punishment
Touma remembering what happened and the two of figuring out the circumstances behind the gag
Touma then remembering the fanservice moment leaving Mikoto as the flustered one. i.e. The punchline is now focused on the girl's misery.

Even the accompanying image isn't focusing on the fanservice! Its just so smartly written and one of the key defining traits of this series that separates it from other generic harem ecchi series. Bravo, Kamachi.