The end of "Cogenitor", where Archer blames Trip for the death of Charles.

Any scene in Discovery where that Michael woman starts crying.

Although I could argue there are worse scenes in general, the one with the most impact for me, that almost cut my Trek fandom short... the handholding jellyfish at the end of TNG's debut 2 parter.

I watched it when it first aired, and I cringed so hard that my family thought I had a stroke. Really, those episodes were full of stuff that made you feel like an ass telling your friend new to Trek that "it gets better," but that really was the whipped cream and cherry on top.

Edit isn't working, so here's a second one https://gfycat.com/coolveneratedfrillneckedlizard That is all.

In the movies I would say when Worf went into Klingon puberty in Star Trek: Insurrection and got a giant pimple in his face that everybody was making fun of.

People often say the Evil Spock episode was memorable, but why? I always thought it was so tropey. It just doesn't strike me as thought-provoking if you can sum up something with "a parallel universe decided to release an evil version of me with an evil beard and nobody else to come from a parallel universe and frame me aboard my ship". That would be more in line with Futurama, and ironically they handled the concept better.

https://tenor.com/view/star-trek-william-shatner-james-kirk-overreacting-wall-gif-4600549

All of Star Trek: Picard.