Many examples of orgs that people thought were too big to fail:

• Blockbuster
• The British Empire
• Kodak - now taken over by digital cameras
• Nintendo - Sony was the first company to beat them in videogame console sales
• Hollywood vs. videogames - I think Grand Theft Auto was the first videogame to earn more revenue than any movie.
• McDonalds - There has to be some years when they didn't have the most revenue or the most locations compared to their competitors
• US automakers - Japanese companies earned more revenue
• Disney - No longer the biggest revenue-earner for animated films
• American comic books - Taken over by Japanese comics
• Cable TV - At its height, there were hundreds of micro-niche, useless channels