This is true. Anecdata, but I talked to some of the “Republicans for Bernie” back then, and it was real, not astroturf. We’d be in a different place if Bernie had been the Dem candidate in 2016. I think it’s likely Bernie’s actual presidency would have been a major shitshow that made Jimmy Carter’s look pretty solid, but it would have relegated Trump to what he originally wanted to be, a fringe political figure grifting millions from gullible conservatives.
(I also think Bernie could not have won in 2020.)