Back in my day, it was Gravitation. But you are right that these aren't the typical old weebs. Old Anime weeb girls didn't colour match their gaming setups - most don't even have those. In the 2000s, when I was growing up, to be a weeb meant you just consoomed ANYTHING Japanese.
Postcards of temples, japanese umbrellas, the Lucky Cat things, anything that had anime on it (posters, bags, wallets, keychains), Tokyopop manga, Shonen Jump, OST CDs. None of this shit matched, mind you. It just had ANIMU on it. Then they'd write fanfiction, do fanart, make their own stickers/keychains, then save up for conventions and cosplay for those - but it wasn't cosplaying for pictures. It was like their Christmas day where they could run around screeching and buying those low quality plushes and such while pretending to be Luffy or Kagome or whatever.
They'd come to school with their Naruto headbands and jackets and say SQUEE OH MY KAMI KAWAII*. They were consoomers but ultimately sort of harmless because even within their friend group, they'd share their mangas between themselves and pirate anime and exchange art. All for free. They didn't ever influence anyone to be like them. The autism was contained within their group and you could easily avoid them.
*Source: I took high school Japanese because fuck French and boy, oh boy, the memories linger from my bad decision.
It wasn't like it is now - an aesthetic for girls to indulge in. To my knowledge, the most coveted thing those weebs wanted back when I was in high school was a bamboo tablet because, like all delusional kids, they were going to become a Manga-ka. First DeviantArt, then JAPAN! But now, my god. $130 for that stupid fucking pixel thing? Multiple pastel keyboards? Desk mats, figures (GoodSmile ones, if I remember, are EXPENSIVE), food carts, mugs, Neon Signs, Gaming Skins for their Switch/Switch Lite/Controllers, etc.
Like the weeaboos of old may have spent $20 on a knockoff bag with Fruits Basket characters on it, but none every spent more than $1000 on a neon sign of Usagi from Sailor Moon stuffing her face with ramen. It just feels like the consoom has been ramped up to 11 with social media and these damn tiktok girls glamorizing dropping thousands on a "look". Like, you can get anime and manga scans for free online, yet the New Weeaboo must not only buy all the boxsets/books, but you got to have the figures/funkos too in a glass case and all colour coordinated with your two Switches nearby to justify why you spent $2000 on a pink gaming setup.
It's actual lunacy.