Yeah but his position (from my limited analysis) was an incredibly dogmatic Marxist position, which despite being wrong wasn't exactly some random crazy idea, especially without the benefit of hindsight. Sacrifice everything for the European revolution because it was more industrially advanced than Russia.
If the Soviet Union had immediately fallen or been crushed by the Nazis (as Trotsky later seemingly wanted to happen????) the idea might have more merit in retrospect. But that didn't happen so he's anti-vindicated. And the like 700k to 7k vote against Trotsky demonstrates that it wasn't supported at the time either.