When did this trend start, this monoculture of design? It seems that nowadays, content and function aren't even important--what's important is getting the right

When did this trend start, this monoculture of design? It seems that nowadays, content and function aren't even important--what's important is getting the right filter, portraying the right "vibe," and using vapid, trendy, copywriting. I write this as someone who's obsessed with design, but who kind of hates myself for it. It seems like people around the world are designing defensively--insecure with themselves and making everything as Squarespace/Stripe lookalikes, to the point where if one does something different, it's considered ugly/bold.