SWTOR's Steam launch was pretty good. The game peaked as high as 30,000 players. It has obviously gone down since then, but it was a great sight to see. Normies will criticize old games despite everything, and I'm sure GW2 would get its fair share of backlash even if the game didn't run like garbage.
And the fact that existing players won't be able to migrate is incredibly moronic. SWTOR and TERA did it without breaking a sweat.