I'm fairly new to Vintage, so take what I say with a truck load of salt. But I find it fascinating as a Dredge player to see the difference in how people respond to Dredge doing well, compared to when Shops does well.
When Dredge does well, it's like this 'break the glass, hit the big red button' kind of moment. It cannot be allowed to happen. People bring in everything short of Withered Wretch to deal with us.
When Shops does well, you see people throw up their hands in frustration, and resign themselves to their fate. You don't see a vast increase in Hurkyl's Recall, or Stony Silence, or Fragmentize.
I understand the argument that Sphere, or Thorn can put a hamper on these plans. But you don't see people stop playing Reanimator simply because Deathrite Shaman exists, or people stop playing Storm because Flusterstorm is a thing. They find ways around it, or they power through it. The argument that Sphere effects are a reason to not even try feels similar to the popular 'Dies to Doom Blade' argument.
This past weekend the meta was incredibly hostile towards Dredge, largely because it was touted as the bogeyman of the tournament. People responded to that threat accordingly. I would like to give these same people a chance to respond to this threat of Shops before I start seriously considering a restriction on Workshop.