I have a CNC mill made in 2006. It's still perfectly fine. It should still be fine in 2036. The most significant threat to its existence is the compatibility of OS drivers and software support in CAM tools. That and USB ports getting replaced by something else, which was a problem for earlier-generation machines that used RS-232.

USB to RS233 adapters should still work for those unless there are really weird timig requirememts.