Games

This is not a good way to look at it. Competition is good regardless. It doesn't matter how good Valve is today, if a viable competitor comes out, Valve will be forced to get better in order to compete.

All we need is some way to guarantee valve doesn’t become public.

This is wrong. Valve can enshittify without going public. If you think that public corporations are the only ones that are greedy/evil/anti-consumer, then you've never heard of the "private equity" industry. Look up the recent fight between the FTC and U.S. Anesthesia Partners in Texas for a clear example.

In capitalism, free market forces are what keep tug of war between produces and consumers fair, and competition is the fuel that keeps those free market forces moving. The fact that the Valve of today is both good and a monopoly is just a temporary rounding error/outlier. Over time, Valve will go to shit and consumers will suffer simply because Valve has almost no competition. This isn't a question, it's a fact of the mechanism of the economic system they exist in. It's like gravity; just because you haven't hit the floor yet doesn't mean jumping off that building was a good idea.

Epic games, whether you hate them or not, is fighting the good fight. They are doing shitty things (exclusivity, etc), so maybe they aren't the chosen one who will take challenge Valve, but they are on the right side of that fight. Hoping that Valve will stay great forever is foolish.

...but I will add that I don't think Epic alone should be trying to take down Valve. Valve is way too entrenched in this market to be taken down with any realistic competition (probably why Epic is resorting to exclusivity deals). The FTC needs to step in and regulate the market. Idk what that would look like, but it's possible to do it in a way that makes everyone happy. For example (off the top of my head, so probably flawed but whatever) the FTC could enforce interoperability between digital marketplaces so that consumers don't need to install 30 different launchers to access their purchased libraries. That relatively small change could lower the bar to entry for competitors by a lot, and not be a burden to consumers at the same time. EDIT: and it would not be anything drastic like forcing a break up of Valve.