To assume anything older than ones own existence is in some way terrible, often expressed by way of displaying an absolute lack of historical events or time-frames. Typically practiced by fans of modern comedians and vloggers/video-essayists who treat such media as some form of unbiased factual source of knowledge upon which to base their own understanding of the recent past, for reasons that are currently unknown. The assumptions built upon these misunderstood media offerings occasionally lead to the assertion that cultural normatives such as gays, women, and racial diversity in media, the mingling of races, and women in the work place, including the achievements of people of those groups were not a thing, therefore did not happen. Effectively erasing them from public knowledge loosing their stories to time.
From the word 'cheugy' meaning something old and out of fashion, and '-phobia' a word often added to the end of other words to pretend the resulting term is a medically recognized physiological disorder until an actual descriptor is found, or another label one likes better comes along.
Young person: "...Yeah, well in your time they had legalized segregation and cocaine in soft drinks too!"
Older person: "In the 90s?! Dude, you're about 50 years off, at least. Also, cocaine and coca leaves are not synonymous. Stop being so cheugphobic, its making you look like a dumbass"
Young person: "Cheugphobic?"
Older person: "Yeah, you're expressing cheugphobia, and it shows how underhandedly oppressive you really are. "
Young person: "Whatever enjoy your shadowban!"
Older person: "Shadowban? Why, so you dont have to deal with the potential confrontation of banning someone publicly?"
Young person: "So I dont have to deal with the potential confrontation of banning someone publicly, yep."