History is littered with endless examples: HP, IBM, GM, Kodak, Sony, Xerox, Sears, Pan Am, US Steel, Nokia.
Some of them collapsed entirely, some still struggle on, some recovered only to rot again. It's rare that mega corps don't go through some variation of a rot cycle due to the accumulation of poor leaders at the top once they get large enough and far enough away from the original vision and leadership that got them to the top.