Why he left Mumford & Sons
In March 2021, Marshall praised Andy Ngo on Twitter for his 2021 book Unmasked, which is deeply critical of the antifa movement, saying "Congratulations @MrAndyNgo. Finally had the time to read your important book. You're a brave man". Marshall's tweet received backlash and criticism on social media.[95] Following this, Marshall apologised and announced he was taking time away from the band.
https://en.wikipedia.org/wiki/Winston_Marshall
Meanwhile the rest of the band
British folk band Mumford & Sons have encouraged Americans to “make a voting plan” as they performed at a campaign rally for Democratic presidential nominee Kamala Harris.
https://uk.news.yahoo.com/mumford-sons-encourage-voting-plan-021208705.html