The only correct answer is the mainstream one, or at least the one that used to be mainstream:
Cowboy Bebop>>> Outlaw Star > Trigun
I'm tempted to remember the anecdote about wisdom of the masses.
There was a researcher who noted that if you ask a lot of people a question like how many jellybeans in a jar, you can get a very good answer by taking the average.
But when the same people are allowed to discuss their answers, suddenly the estimates are much worse.
The early anime fandom independently and correctly identifies Cowboy Bebop as the standout and the superior among the 3 shows.
But now 20-30 years of stupid people talking, and bad arguments proliferating, we are seeing people disrespect Bebop, and put the other 2 shows above it.