That’s a bummer, but from what I heard it is better that way. Jim Marshall is a legend. His amplifiers have revolutionized music. Period. I truly believe that without him, blues, rock and heavy metal would have never evolved to where they are now. I’m not going to recite all the famous guitarist who used and still rely on Marshall Amps – I guess the more appropriate question has to be who doesn’t use Marshall.
Jim died of cancer after also suffering from a serious of strokes, at 88 years of age. His family publicly stated that his health deteriorated drastically over the past few weeks and that he’s now “at a better place”.
For what it’s worth, I was always a fan of Marshall amps and I never played any other brand. Here’s my setup – admittedly rather modest, but still plenty of “bite”:

Thanks for everything, Mr. Jim Marshall and rest in peace. You’re a hero.
Godspeed.