I find that there is a wave for these kind of things. From an ex-seller it goes like this.

Game starts in life at MSRP, and loses value based on how in demand the game is. The better the game the more it holds it’s value. i.e. Vita games MSRP for like $39.99 would cost between $29.99 - $19.99 used in the first year.

Then it becomes “uncool” and the Value plummets to it’s lowest. Typically this happens when the platform becomes abandoned or the games become old news. i.e. the value of an old Call of Duty after about 1-2 new releases. There is a rare exception to this rule, when a game becomes a tool or a meme, in which case the value will skyrocket i.e. Hanna Montana the game on PSP.

Then the game will sit there and the true value of the game will be determined based on: how good the game was, how many copies of it existed, and if a series got popular after the initial release. Think Persona 4 Golden on Vita, Pokemon Cristal on GBC or Conkers Bad Fur Day on N64.

Then finally the demand will rise again when teenagers, who now have disposable income, want to re-live their childhood, or get games they couldn’t before and start buying the cheap games. Rising the value of the in demand and popular games.

A feeding frenzy happens and the values will go through the roof, then eventually settle down. Eventually returning to a stable price. Typically more than the lowest, but unless the demand outgrew the supply not above the original MSRP or the current MSRP of the current gen.

COVID was an interesting experience because of the increased demand, but thankfully for the common games the price is lowering.