It's not even close to essential, since by far the majority of businesses are running without anything close to what people on HN would consider adequate. It only becomes a problem if too many of your competitors have good tech and even then only if your industry depends on (software) tech. Companies like bakeries and building contractors can run fine with shitty IT and even if their competitors do IT better, no customer is going to drive further to get a bread from someone who has proper backups instead of from the closest shop.