To me, the solution to this is simple: if you eol a product that renders it useless, open source it. Allow someone else to support it and perhaps at a profit. The same would happen if a phone or cable company decided to drop and unprofitable area.
Maybe it runs on Oracle. Maybe it has third-party stuff licensed for their use but not open source distribution.
Rather it's the third-party proprietary stuff. Someone else owns proprietary code you deeply rely on but doesn't share any of your business goals and needs. And when dealing with hardware, there is a whole raft of firmware and drivers that could be licensed this way.