I have been downloading games from itch.io for almost a year now and I dont mind to pay if the price is reasonable. Lately I saw that some developer ask insane prices. There is no way I will pay $USD 20,- or $USD 50,- for a game that can be played in a few hours as long as there are better games for free or for small money that take days to finish. I understand that the developers want to by payed for the time and the efforts but  actually the market dictates the prices.

It can't be helped. You might want to wait for reviews for expensive games first before deciding to buy any of them or not.

Depending on the game, between 20 and 50 dollars is usually the correct market price in the USA and Europe.

If you live in a different area, for example Russia or Brazil, stores like steam or gog have reduced prices and there, 20 to 50 dollars is usually above the market average. The problem in that case is not the price set by the developer, but rather that Itch charges the same value to everyone.

They may have calculated typical downloads and set an appropriate price, which means you’re not in their market.

Sometimes when games are overpriced here, they're available elsewhere cheaper - like on Steam or Patreon. The overprice on itch.io is to advertise the game here - but get the person to conclude the purchase elsewhere.