I'm going to nominate Badfinger. While some of you may be familiar with their story, for everyone else, read this... https://www.google.com/amp/s/www.loudersound.com/amp/features/badfinger-bad-breaks-dumb-luck-tragedy-peter-ham I still think 'No Matter What' is one of the greatest power-pop tracks ever. My second nomination would go to the Allman Brothers band, specifically Duane. Bandleader Duane Allman Dies in Bike Crash
Fairport Convention's bus crash in 1969 which left drummer Martin Lamble and another passenger dead and the rest of the band injured and traumatised. They went on to record their classic album Liege and Lief later in the same year. The Day Fairport Convention's Bus Crashed, Killing Martin Lamble
Judee Sill. Spine-tingling music, only to come to a tragic demise due to intense physical discomfort and drug use, a death which - some subsequently remarked - went almost unnoticed at the time.
Def Leppard have had more than the occasional bump in the road, yet keep their heads down and just get on with it. Class album after class album. 'Nuff respect!
Jim Croce holds kind of a special place in sadness for me, because some of his songs were so sad, and then he died in such tragic fashion.
Randy Rhodes Cliff Burton Kurt Cobain Stiv Bators Richie Valens Ronnie Van Zant Bon Scott Jason Becker To name a few.... So many more.