I wouldn't say they get replaced...that makes it seem like kids are the ones that buy consoles the most.
I feel like somehow i started with PSOne in 1998 when i turned 10, when i was gifted one...and Sony has always been "by my side" ever since. I do think consoles do a little bit of everything: trying to get a younger audience while preserving the older generations that had already acquired previous consoles.
I'm sure PSOne didn't have as many 35 year olds playing it as the PS4 had, and so on.
The fact that you were 10 years old, when you got the ps1 shows it. You stuck with them since that day. That is how kids are. If they get attached to something at young age, they are stuck with that.
Also, kids get consoles from their parents. At the age of 16-18, they start working and saving money for the new console. 1st they do with their money, is spend money on that console. And since kids are not that smart, they will buy tons of games.
Look at us. We are old, and the 1st thing we do is buy cheap games. Even the good games, we wait them for sales. We know the value of money. Kids that age, lack control of spending.
My little brother is 19 years old. I bought him his ps4 in 2017. Last year, I bought him $750 ps5, which he gave me the money later. This year, he spent 1.5k easily on a pc gaming.
My pc cost $500. And he spent $1.5k on his pc. All he plays is warzone, fortnite, and call of duty with his friends. That is how stupid kids are these days.
These are what Sony/Nintendo/MS want. People like him, will gladly spend alot of money on their console. Especially their headsets, extra controllers and other stuff.