I'm not underestimatin' Sticky Web; you'll see it on my team, I can tell ya that much. I'm not underestimatin' Shuckle either, 'cause it sucks. Nor are you overestimatin' Sticky Web, as it's definitely gonna be crucial to the metagame. It's a matter of you overestimating Shuckle. What can it effectively do 'sides Sticky Web? Rocks, Toxistall and Encore. Three things a shitton of other Pokes do better to the point they're worth an extra team slot. It's still Taunt and 'specially set-up fodder when found without Encore.
Galvantula is gonna be everywhere abusin' it's accurate Thunder 'n Sticky Web, everyone's gonna have a speedy Taunter/hard t' KO spinner, as well as entry hazards of their own to kill said Bug-type. Oh, and stall will be more viable since it gives few-to-no ****s 'bout losin' speed.
Oh, and let's not forget that Levitaters or Flyin'-types don't care 'bout the entry hazard. And priority. And Quiver/DD.