You see, they are NOT tech companies. They have something you would call "tech", they sell something that looks like "tech" but they really solve problems people with access to large amounts of money have.
In other words, they produce cushy and warm beds for C-level execs to have a good night of sleep, and everyone needs some bed to sleep every night..
Technology is a risky and volatile business and IBM has more than 100 years in business.