sadly gaming has moved away from buy and keep
its all monthly subscribtions, or day 1 DLC, addon packs etc...
In the 1970's, you could get a new computer game for $60 (example? SSI's 'Bismark' wargame. Or look at the original Infocom text game list prices).
Products adapt to inflation. Gaming not only has inflation but increased production costs. Apogee could release VGA graphics - today's games need a lot more technology.
So, if the game just kept up with inflation you could pay $150 - add in the increased technology, make it several hundred - and then adjust to the culture of discounting that has crept up. It's not 'sell at the retail price a very long time', it's most people expecting a huge discount soon after release, and waiting for one.
Games didn't used to need millions for a development budget and now a lot do. The industry is bigger than Hollywood, and the big titles have big costs.
Customers won't spend the hundreds on the game to adapt by increasing the price.
What they DO do is reward games that give them a game they want to play long enough that they're willing to pay more again and again for more things in the game.
It also does mean day 1 DLC - because as unpleasant as it might be, it works better with customers than the alternatives of increasing the game price to include the DLC for free, or not offering the DLC at all, or pointlessly delaying the release of the DLC - yes, it's a calculated marketing move to get money. What would you have them do instead other than work for free?
As ugly as any of the practices seem, I see them rewarded by customers, who could but won't reward, say, a massive, expensive game with a big budget and big one-time price.
Money talks.
I use my experience with World of Tanks as an example - I probably wouldn't have paid $30 for it to start, but playing years, ended up spending hundreds of dollars, and have to admit that it was more effective than any other way I can think of for them to get the 'value' of the game paid to them.
Long ago I thought 'they should make better games with huge budgets that cost hundreds of dollars', but the market just doesn't support it - and despite my support for the idea, I'm unlikely to actually buy such a game without a really good case. These models, though, 'work' for getting customers to pay.
If you bought a $30 game and loved playing it for years, did the developed get paid an amount matching the value you got? No.
And games designed for long-time play with big budgets have a competitive advantage over one-time purchase games with smaller budgets.