The clip comes from the French word atroce, meaning atrocious, stretched online into atroceeeee for comic effect. The existing caption sums up its tone as completely atrociously atrocious, which captures how French speaking users share it as a hyperbolic insult for anything unpleasant. Short reaction clips like this spread through soundboards and short form edits because the meaning survives translation, the drawn out ending is easy to recognise, and it can be dropped over almost any fail, flop or disgusting moment without extra context.
Sobre este som
A short French voice clip shouting atroceeeee, meaning completely atrocious, used as an exaggerated reaction to something awful, cringe or painfully bad.
A stretched, shouted delivery of the French word atroce turns a simple complaint into pure melodrama. The voice drags out the final syllable in atroceeeee, getting louder and more theatrical as it goes, so even a minor annoyance sounds like a catastrophe. It works because the exaggeration is instant and unmistakable, even for listeners who do not speak French. The horror is never real, it is performative disgust, mock outrage and comic suffering rolled into one short burst that lands perfectly over a shocked face or a terrible reveal.