For the one that wonder who is using mainframes nowadays: most banks, insurances, airlines, grocery stores, public administrations still have something running

For the one that wonder who is using mainframes nowadays: most banks, insurances, airlines, grocery stores, public administrations still have something running on a mainframe, maybe in their datacenter or in some outsourcer one's. From a technical point of view, mainframes are really awesome and many things people speak about today thinking it's something revolutionary were already a thing in the 90s (or even earlier) on the mainframe, for e.g. "serverless". But basically no one is starting a new business on a mainframe, and all sells IBM is still doing are on existing clients. It's a slowly dying tech.