I think it would be more accurate to say Crosby was a founding member of the Byrds. And before the Byrds, there was The Beefeaters (McGuinn, Clark, and Crosby).
My regret was that the Byrds appear never to have recorded "Mr. Tambouring Man" in its complete form. Dylan's incredible poetry and the Byrds' great vocals, it was a perfect combination, but sadly in complete form, it was too long for a single, and the best lines were left out.
Yes, to dance beneath the diamond sky
With one hand waving free
Silhouetted by the sea
Circled by the circus sands
With all memory and fate
Driven deep beneath the waves
Let me forget about today until tomorrow
Anyway, I will grudgingly give Crosby a pass on his political views, and hope he has found peace.
“My Back Pages” - my favorite Byrds song although their studio version cut many of the verses...like they did to Mr Tambourine Man
“My Back Pages” - LIVE complete song led by Roger/Jim McGuinn with help from Tom Petty, Neil Young, Eric Clapton, George Harrison...and Dylan
https://www.youtube.com/watch?v=rGEIMCWob3U