I just clocked it that Thanos never hated the Avengers, he pitied them.
Look at the way Thanos treats the heroes on Titan and in Wakanda.
He doesn't talk down to them, insult their power, or celebrate when he wins.
When he stabs Tony Stark, he doesn't gloat. He cradles his head and says, "I hope they remember you."
When Wanda is forced to destroy Vision, he steps up, pats her head, and tells her he understands loss better than anyone.
Thanos didn't view the Avengers as enemies standing in his way.
He viewed them as tragic, misguided children who simply lacked the stomach to do what was necessary to save the universe.
That cold, fatherly sympathy is what made him ten times more terrifying than a villain who just wanted to conquer everything.