First, Facebook should charge users a nominal $5-a-month fee. You can give seniors a discount so you don’t lose them.
Netflix does, Amazon does, Apple does. It would make Facebook rely less on selling user data.
While this will not totally eliminate nefarious acts on the platform, it does provide a paper trail to track bad actors.
Second, split the company in two and spin off Instagram. It’s probably worth more than the original Facebook platform anyway, and it will stop the corporate contagion from spreading and polluting that category champ.