1. Taxing those outside investors too
2. Taxing Valve as a corporation more, making them less profitable and less attractive to said investors.
3. I’m not even convinced this would be an issue at all really. Remember Valve is not publicly traded. I suspect Gabe would hold on to controlling ownership as long as it was profitable, and remember that taxes are usually on profits.
4. Even if outside investors move in and enshittify, the moment they start doing anticompetitive you hit them with antitrust suits. Not to mention the industry can also be regulated even before all this: a lot of governments are cracking down on lootboxes already.

Even if Valve’s offering sucked, I still have not seen anyone point out a business practice I would call anticompetitive. They are not buying up studios or publishers, or even paying for timed exclusivity. I have not seen any hint that they are colluding with competitors on prices or fees. I haven’t seen then accused of stealing IP or poaching personnel. They readily welcome Microsoft and Sony to release games on Steam, and they have released their own games on consoles including the Switch. They let you install Windows or whatever else on the Deck, if you want to for some reason.

Billionaires should not exist, and Gabe Newell is no exception. He should be taxed more. I don’t love one company having so much control of this space. But I also don’t want to have a dozen different crappy launchers from different companies to deal with. There are a lot of benefits to the user to having everything centralized in one place.