There were tons of platformers this gen, but it's easy to forget that since many were so forgettable IMO.
Last generation when Mario64 came out, I couldn't believe what I was seeing and couldn't wait to play something else with similar design. Then Banjo came, with even larger levels and environments and again I was amazed wanting more. 3D platformers seemed like there were going to be where it's at for years, and I even wished the PSX was more powerful so I could see even more developers could get in on this action.
Then Donkey Kong 64 came out.
Then all of a sudden I got tired of platformers. Who knew that collecting a bazillion bananas could do that, but it did. Banjo Tooie was just as bad. Conker was a breath of fresh air, but it was almost too little too late at the time.
This gen because of stronger hardware we've seen MANY new platformers, but nothing with a successful unique approach to make them stand out IMO. Just remakes of ideas already done, but this time with good draw distance and crisp visuals. That's part of the reason why Mario64's sequel, while pretty solid in controls and platforming, got somewhat of a lukewarm response as well. Just not enough to make people think they needed to have it. We've collected before, we've hopped around before,...what now?
Jak and Ratchets weaponry and sense of style brings them to the top of the heap, but I just kinda dragged myself through those games as well. Sly was ok, but I don't feel the need to play the sequel. Sonic has gotten worse with each iteration. Won't be surprised if my favorite platforming experience this gen comes from Conker, a port from last gen