I'm inclined to disagree on the basis that, even whilst still relatively young, Coldplay have a sound that is much more their own, rather than one that is so heavily laden with the delivery style of a particularly well-known '60s group.
Oasis were never more prophetic than in the titling of their album- 'Standing On The Shoulder of Giants'.
In terms of the music and songwriting itself, I feel that Coldplay are infinitely more interesting than Oasis and are a more promising band in terms of breaking new ground in music than Oasis ever were (or weren't, as it turned out).
Oasis were assisted in their rise to the top by many factors, amongst them the polarisation of the music scene at the time between themselves and Blur (rockers vs. mods, anyone?).
Oasis were also great at courting media attention thanks to the attention-grabbing antics and excesses of the brothers and their intentionally anything-but-private lives.
I have the strong suspicion that, by contrast, Coldplay would prefer to (and no doubt, will) achieve greatness much more through genuine merit than media manipulation.
...imho.