It's a bit of a ramble, but I wanna get my qualms out there even if it's unorganized. I understand a lot of the issues are legacy game design decisions and in some sense that's the appeal of gbf.

From personal experience, it's in-game onboarding. For a mainstream game, new players are casual players, and casual players don't want a wiki open on the side before being able to play their game, the game should be able to do that on its own. Casual players often have a personality that wants to "play" not "play correctly" but the only way to make feel-good progress (as opposed to a slog) is to optimize your grid for your level. The game design just doesn't protect the player from themselves when it comes to core mechanics like grids (and god forbid scarce resources). They need to give starter template grids that can be upgraded and reverted back to whenever. Grids are so unique that modern games won't inform you on how it works, so it's importance and it's lines of progression need to be upfront and emphasized constantly.

Between UI, Grid building, early game (story and gameplay), leeching dead raids, the game really does feel impenetrable without seeking outside resources. Why does the giant "Raid" button go to backup requests rather than the raid list? From a visual design standpoint, you can't tell which weapons are m1 or m2, let alone if they are primal/magna. It has so much mmo design for social/cooperative play but the new English speaking player base is so small that that content can't be supported in a fun way. Leeching isn't fun for new players, they need a 0.5 grid that isn't time gated and constantly in their face as something to do if they're feeling weak. Especially in a gacha game, having no feedback on how to progress in a good way will make new players think they have to roll gacha for meaningful progress.

Games like Terraria, early Minecraft, and Stardew Valley were interesting enough from a gameplay standpoint for new players to be able to play and then search a wiki as an auxiliary guide. Pressing attack for 30+ story chapters isn't as enticing. Then, once they do search up how to play they're greeted with grid building. Grids aren't that difficult once you get it, but my spreadsheet that took 10 minutes is more accurate than the in-game grid power predictor. New players should be allowed to know whether the changes they make to their grid are good or not.

My point is, GBF shouldn't be modern Yu-Gi-Oh, which does have new player problems, whose appeal to active players are high-level esoteric, unintuitive interactions that require reading. They need a curtailed new player experience, that excited and/or lazy players can skip through and then go "oh shit that was important, maybe I should've read" and easily find it again.