I don't think Test Track gets a lot of hate actually. I've yet to ride the new version with the Tron like lighting (looks like an improvement over the first one at least), but still not a big fan. Even less when I consider what we lost to gain it. To me it was just a way to satisfy people who thought the park needed a thrill ride. I'm not really again that, but it should have been an addition, definitely not a replacement to the current roster of rides.
If it was really necessary, they should have just built the ride around the general area of the World of Motion building, not inside. I gather that this was one of the original concepts when the park was in concept stage. From Martin's tribute on WoM, looks like a Test Track type of ride was going to travel around the WoM building (perhaps through it in parts and intersecting with the ride inside), but both were going to be separate rides. That would have been a much better way of dealing with the situation and would have pleased pretty much everyone.
And yes people probably wouldn't have hated so much on Test Track had it been an opening day attraction. If there was never a World of Motion to begin with, there wouldn't be anything to compare it to. Though it still doesn't compare to other rides like Horizons or Spaceship Earth. To me, it would have been a tolerable addition to the area had they kept World of Motion as it was (obviously any SSE'94 refurb would have been welcome to all the Epcot rides though), not replacing it.