I think this has to do with the DM not shining the spotlight on the PCs or the PCs not taking the initiative to shine by trying to do things that are cool, outside the box, or out cinematic.
I've DM'd quite a few 4E games and each and every character can "shine."
Tanks - Shining by doing their interrupts as [MENTION=100080]Locutus Zero[/MENTION] stated or by being able to absorb a bunch of hits. My previous campaign we had a paladin that marked very well and tactically, he'd shine every time when the monsters he marked decided not to hit him and go after someone else, they'd take a certain amount of damage for just doing that.
Strikers - I had a rouge sniper drow in my group who always nailed everything for a lot of damage, yep that's shining too, he was a smart player who really went into his character to get the most out of being able to use his surroundings to be able to snipe from afar and gain concealment again and again. Had another striker in the group who was a halfling rogue - he didn't do a lot of damage, but he was awesome with his tumbling abilities and whenever he tumbled by something he'd create AO's at -'s then if something missed he'd nail them. He also liked to climb up on the back of large or bigger creatures and cause them tons of confusion or turns to try to get him off their backs! Made for some great funny moments.
Leaders - Had a warlord in the party who was amazing at controlling the battlefield, he would stop me in mid sentence "not so fast..." and then position people everywhere around the map and ruin some good plans I had in store for the group.
I had a cleric in the group too, he'd bring people back from the brink of death up to full hit points, he'd throw some damage over time spells on things and buff up the group. Another smart player who got the spotlight.
See, it comes down to how YOUR players play the game and how YOU react to it as a DM. I encouraged them to think more creatively and rewarded them when they did so by giving out an extra action point or something else that I thought was cool or appropriate.
As always, just have fun playing!