Ha, we'll have to talk this one over at DCC Stu!
Big differences between the two. Many of the world championships that Willie won were in round robin formats where they would play long blocks of straight pool against groups of many other players. Alternatively there were championships decided where the contender would play a long block to over 1,000 points. In his autobiography Willie talked about how much he hated winning the title in that fashion and then losing the title when the BCA decided to do a one game finals so someone else is crowned with one good run. The world championships today, while extremely coveted and prestigious, don't define the best player in the world anymore than they did in the years someone beat Willie one game of straight pool. If we want to keep score that way we can, but we can't equate the two formats.
In addition pool was strictly a US game and Willie was competing against the same group with only a few real challengers. The US Open 9 ball today is far more international than the world championships of the 40s and 50s.
I'm not making the case that SVB is better or worse than Willie, only that contrasting the number of world championships they have both won isn't a fair measuring stick and for the reasons above no one will come close to duplicating WM's world titles.
Personally I think SVB joins the ranks of Reyes with players that not only dominated the competition, but that transformed the game. Many players have gotten to the top, and a few have even dominated for a stretch of years. But only Reyes and SVB left the game looking differently after they exerted their influence. SVB made his opponents look silly in 2007-2012. Suddenly in the 2015-2020 range we have a slew of global players that break like machines and seem to shoot as good as him (although lacking a little in experience). This isn't a coincidence. All of the players that were up and coming teenagers in 2007-2012 used him as a template and the result is that pool is tougher now than ever before.
I can't give him all the credit for this, pool would've evolved without SVB just like kicking would've evolved without Reyes in the 80s and 90s. But I believe SVB to be one of the most influential pool players of all time. I'm a huge fan of Varner, Hall, Strickland, Alex, and the rest of the greats, but I don't see the impact they had on pool the same way. Add that to his dominance domestically and globally and you'll understand why SVB is on my Mt Rushmore next to Reyes.