Most companies I have seen have never updated the BIOS of their servers, nor the firmware on their switches. Some of those have production applications on Windows XP or older and you can see VMware ESXi < 6.5 still in the wild. The same for all kinds of other systems including Oracle Linux 5.5 with some ancient Oracle DB like 10g or something, that was the case like 5 years ago but I don't think the company has migrated away completely to this day.
Any sufficiently old company will accrete systems and approaches of various vintages over time only very slowly ripping out some of those systems. Usually what happens is that parts of old systems or old workarounds will live on for decades after they have been supposedly decommissioned. I had a colleague who was using CRT monitors in 2020 with computers of similar vintage, probably with Pentium III or early Pentium IV, because he had everything set up there and it just worked for what he was doing. I don't admire it, yet that stuff works and I do respect that people don't want to replace expensive systems just because they are out of support, when they do actually work and they have people taking care of them.