Apple seems to be still around. You can google it to check. Apple's problem with PC was initially simply that IBM sold the PC. For many years PCs were more or comparably expensive and much less useful than Macs, but sold because they were backed by IBM. And Apple did very well despite its lower market share until John Sculley started listening to pundits and lowered prices in the early 90s. Even so that worked Ok until Spindler listened to more pundits and started allowing clones.
Apple sued their clones out of existence. Might all be using Apple today if they had not.
Then they eventually switched to pc hardware themselves.