Honestly not surprising based off the decks they we're playing.
For a bit of Yu-Gi-Oh autism and personal opinion, evil twins was always going to be the better deck because of multiple reasons. Though don't get me wrong both decks can be strong, eldlich is better as a stun deck in my opinion, which I'm going to assume biboo didn't build as it's pretty slow, boring, and frustrating to go against. It got two inherit flaws that make it the worse deck, those being it's a trap deck and the golden lord himself.
Trap decks by their nature are inherently slow as you have to usually wait till your next turn or your opponent turn to use them, now this isn't always true as Konami sometimes makes it so you can set and use them that same turn Labyrinth for example. The other flaw being the Eldlich the Golden Lord is because the deck is very over reliant on him, which goes back to the traps and spell. If you don't have him on field you loose the other benefits of the traps or able to summon something else to extend your board. Not to mention both forms of the golden lord have next to no protection on themselves, and not a sold way to OTK.
The Evil twins on the other hand are just the better deck as it like to spam out monster, usually can play through disruptions, and link climb. I would say they can lean towards a bit of a glass cannon but it can sometimes push though it. The twins are constantly able to search the other out and reviving the other if they get destroyed, even using extra copies of themselves at times to get the other on board only to revive it and then draw or pop something. Even after they get to the technical boss monster, Trouble Sunny, it's better used as disruption and otk set up as it can tribute itself to summon the twins back in the field and because they can come out at the same time they both get their effects as well. Even the spells and traps good for starters or extenders depending on what you need them to be but usually are for taxes or disruption. Just in archetype evil twins are better, but can be even stronger if you combine them with sprights as they add in more disruption and grind game.
Thats my autism on this and probably wrong on some aspects. I don't particularly like playing ether deck but that's just preference. Though I do think if ether of them played more towards there characters lore, Evil twins or Melfy or Purrly works for Fuwamoco, while for Biboo, Tistin or Ashened or Adamancipator.
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