huh, interesting point - I wonder if most kids nowadays could handle the games we played when we were kids.
Shadow of the Colossus had superb boss fights. YOU had to find the darn thing first, THEN start climbing on it until you found the weakspot, THEN stab it and hold on and pray that your grip didn't expire. Now those were some fun bosses.
Dragon's Dogma also has very fun world minibosses. Taking on a Chimera in the forest or a Cyclops on the beach at night is quite a fight.
Touhou Project is definitely great at making bosses. Every level of every game has a boss in it.
And those late game bosses? Tough as nails. Even on easy.
I think the problem with boss fights nowadays is that they are hard (sometimes more lame than hard) only when you set the difficulty to the max (which you usually unlock after one playthrough).
Dude, dude, dude, dude... hold up, RE5 quick time events were hard as hell. On the highest difficulty with a friend online i sweat on the quick pressing sequencies, the tip of my index finger became flat, and we had to pause the game to recover. They aren't always easy or bad, altough I too prefer avoiding them sometimes.
Dark Souls and Demon's souls (and to some Extent MGS 4 on extreme) are the only games which challenge me during boss fights which aren't 16-bit games....