> incorporate elements of glitch, retro, video-game saturated colors
This doesn't seem related to the ethos of "real" brutalism, nor Neo-brutalism.
> modernslick web design, these creations invoke something similar to the spirit of brutalist.
How? Because people generally find them unappealing?
Brutalism is a minimalist movement characterized by showing the raw construction and function over superfluous elements and design flourishes.
Neo-brutalism is a similarly minimalist design style that focuses more on color and layout, but caries with it the simple and clear construction, with simple shapes and typography.
Adding "glitch" and retro video game references seems directly opposed to the core intent of both movements, both the minimalist nature, and the shying away from superfluous decorations. Even the user of Emoji iconography instead of plain text is non-brutalist. Neo-brutalism the re-imaginated design movement carries the original ethos with its focus on the raw elements that make up the design (eg. typography) over decoration. The classic gumroad example is a perfect demonstration - clear, focused typography, boxes with simple, stark borders to delimit various UI elements, etc.
I feel like I can say this because I'm Gen-Z, and not some old man yelling at the clouds, but let's not use the name of random styles to reference new and unrelated styles.