isnt the chess puzzle rating system, unfair?

Wow, that's unfair. But then again I don't even play puzzles like that.

It's actually much fairer than it used to be. The rating is now based on a proper Elo rating system like your Blitz (etc) rating is based on. The default set up is to present puzzles a fair bit lower than your ability, so you should be able to get a lot more right, but like when you play a lower rated player, (who you'd be expected to beat) you don't gain so much if you win, and if you lose your rating will drop by more. If you don't like this, there is now a difficulty setting so if you want to get puzzles around your rating you can change the setting to "extra hard" - this would mean you would lose/gain about the same rating depending on whether your get the puzzle wrong or right, but still using the same fair rating system