Nope, that webbing is meant to bounce you up, they somehow were able to break that behaviour, if there were no spiders there, the game would be uncompleteable.
As for Revolution, I'd disagree, Dreamcast has the frame rate advantage, but when it comes to pure visuals, there's much more detail and objects in Revolution, compare the Rayman models from each for instance, Revolution's actually has the detail on the shoes stick out as opposed to just being textured. As for the overworld being the only thing...eeh, not entirely, while it's true Revolution is pretty much Rayman 2 with an overworld, there's actually been a few additions here and there, Grolem 13 and the Biditank for instance never saw use in any of the original Rayman 2 versions.