I don't see it. I've only seen one match I'd legit say was a good/great match and that was against CM Punk. And honestly I'd say that 80% Punk.
Even in 2002/2003 I wouldn't say he could be a MOTN guy but his work ethic was much higher. Now a days his routine is get beat up for most of the match then pull a Hogan with a hulk up and do the EXACT formula every time. Punch, punch, kick, clothesline, duck, ropes, shoulder block, shoulder block, Prototype side slam, 5 knuckle shuffle, FU if reversed STFU. Rinse and repeat if there's no finish.
Cena literally works the same match week in and week out.
I see where you're coming from, but over the past couple of years, I've enjoyed a lot more Cena matches now than back then.
Also, his match against HBK in England was fantastic. Their match at 'Mania 23 was very good. His match against Umaga at Royal Rumble 2008 was so great as well. So I think he's got some 3 1/2, 4 star matches under his belt.