Even before you get to "value to shareholders" you have to actually pay your developer salaries to update the game. Where does that money come from when you're updating a game that's been on the market for 10 years and sales of new copies have tapered off?
Free major updates make your existing customers happy but don't pay salaries. This is why so many games have moved to some kind of ongoing revenue model with Battle Passes, cosmetics, item marketplaces, etc.
This is one reason why we should either cut back copyright to more like 10-15 years and require source escrow (so public domain materials can come with source) to obtain copyright, or just require all computer programs come with source code as part of consumer protection laws. Then people can fix the engine themselves, or find a way to fund someone to do it.
Or just eliminate copyright entirely and focus on economic models that are based on funding creation. You raise money to build the thing, and once it's built, it's there for all.
In most cases I would agree with you but ultimately games get older and can’t be sustained forever without people being compensated. People don’t pay for DLC like they pay for sequels, as the other person said.
It’s not about shareholders necessarily. It’s also about sustainability and people paying bills - they live in a capitalist society and can’t choose not to participate at the end of the day. You can’t ask a dozen or more developers to keep working on a game for free for a decade or more. They have to eat too.
The only other option is keep playing the exact same game with little to no changes. Which you can! The original is still available. But if you want it to improve and change over time or receive substantial DLC’s, somebody has to get paid at some point.
I don’t want to harp on as you had a couple answers on this already but if you need to pay your devs, what is your suggested alternative to “having money in the bank”? The latter only happens with more sales, and that only happens if you have something to sell.