Its a mix of things.

• Part of it is that studios tend to price their games closer to what they are “worth”. So you have far fewer “This is a 20 dollar game we are gonna try to sell for 50”. They just put it at 20 to begin with (or get there pretty quick after launch). Which means that the same “get this for 10 bucks” is now 50% off instead of 80% off and so forth
• Part of it is that game dev has gotten more expensive at all scales and all selling Big Rigs 1 for 5 dollars will do is prevent people from buying Big Rigs 6 for 30
• Part of it is that… as you get older you are more likely to buy the games you want when they are “good enough” rather than waiting until EVERYTHING is at a max discount so you can spread the money you got from the banana stand over the summer as far as possible.
• Which ALSO means that you have a huge backlog and it is a lot easier to say “Do I really need this?”