OKAY SO. If you, like me, are stuck using Chrome for work reasons (I use firefox for everything else), here's what you should actually do:
On Google Chrome, type in chrome://settings and hit Enter. Using the search bar on this page, run a search for "AI". I don't care that you've done this in the past already, they quiet added the shitty option recently. Scroll almost ALL the way down and look for the On-device AI option, and toggle it off. The bastard's on by default.
Just to be safe, you can go through all the OTHER hits you got on that search and turn anything fishy off. Yes, this includes the spellcheck and grammar check in some instances. It's wild. You know how people keep complaining that Google gives them shitty "corrections" these days? It's crowdsourced AI, and no longer a dictionary and grammar ruleset. Unfortunately this is powered by the way people write, and people are not good at writing unless they are professionals. Anyway.
Now that you've turned off the On-device AI, go back to the search bar on Chrome and type in chrome://flags and hit enter. This will bring you to Chrome's bullshit experimental features, most of which are on by Default without asking. Fun!
Using the search bar on this page, search for "Enables Optimization Guide on Device" and set it to Disabled, then look for "Prompt API" and set both options to Disabled.
If you know what you're doing, run a search for AI AND a search for Gemini and Disable anything that looks off to you. If you don't know what you're doing, maybe don't touch anything if you're not sure what it does xD
Now that you've toggled those options off, you're going to want to open Windows Explorer and type in %LocalAppData% and follow the path @pirateprincessjess noted: C:\Users\\AppData\Local\Google\Chrome\User Data\OptGuideOnDeviceModel\[DATE]\
Delete the weights.bin file from this folder and clear your recycle bin
DO NOTE, if you DON'T turn off the On-device AI option from the settings as I explained in step one, the malware weights.bin file will redownload itself. I know this because it happened to me and I had to go digging.
If you followed every step here, you should be good!
I did all of this yesterday after finding that the 4GB file had redownloaded itself onto my computer and I've been monitoring my appdata folder since (it's been clean so far after a full 8 hours of work!). Still, it might be a good idea to keep checking back just in case Google tries to pull some kind of new shit without our knowledge.
YES I know that getting rid of Chrome altogether is the best option. Some of us can't. This is the workaround for that. Fuck Google and fuck Google Chrome.
OH, and don't use any Chromium-based browsers either. That's most browsers, by the way.
If you can switch to Firefox, do so now. Don't wait. It takes two minutes to migrate, you have access to a ton of extensions for privacy, and it has a built-in AI killswitch now. It will import all of your bookmarks and stuff. You have nothing to lose and everything to gain.