Why do Bethesda accounts still exist?

Because the difficulty and expense of changing the system, and the risk of messing something up is high

In most cases the accounts weren't necessary to begin with and could just be patched out, just like when the clowns tried to require one for the retro Doom games a few years back. Yet, MS isn't doing it. MS is even publishing new games that still use the old account system instead of moving forward. I see zero effort to get rid of it and make things easier for users in spite of all the layoffs and consolidation we keep hearing about internally over there. Someone needs to push the powers that be to deal with this nonsense.

p.s. The Xbox store isn't even warning anyone about those accounts being required anymore for some reason. Other publishers' games have a warning on the store page about accounts.

Because the difficulty and expense of changing the system, and the risk of messing something up is high

No they really can't

Short version- If it aint broke don't fix it. I don't think you understand the things that can happen when you begin messing with databases

Every major publisher requires accounts, it's nothing new.

I know a lot of the mod makers for the weapons I'm using are waiting for the geck to release, they are doing a cracking job without it tbh, there is just some things they can't do yet. I think a lot of the current mods will be updated with the geck.

Details are still pretty non-existant on how Bethesda are going to accomplish it though.

Bethesda, the developer, is constantly working on updates to fix problems. The only bad thing about that, is each update only prevents more known problems from occuring, and any glitch you've encountered will still exist on a current save.