The irony of it all is the same people that designed and make the beaglebone black at $78 are the same people making the IC's in late model pinbals...
Texas Instruments,so the same argument can be used in 10yrs time about obsolete parts.There are already parts no longer produced that have been used in the Stern Sam system,also custom PIC's on Whitestar and Sam systems.
Chips are made for many years, and yes eventually become obsolete too. But boards made for a general market become obsolete much faster, to keep up with competition.
All the manufacture needs to do to stuff things up is do a simple improvement like change put all the connectors on a different side, and suddenly all you cables don't reach! There are many 'improvements' a supplier can do that require the pinball manufacture to do a redesign. The three USB ports that you use, might get cut to two. The Standard Definition output might go to UHD, requiring you to do more with the software that now means the processor is to slow. The list goes on. ...risk, risk, risk.
With all due respect mate I dont think you know what your talking about here, BBB has only 1 USB port and at this stage looks like it is only going to be used for software upgrades and is not used to interface with any part of the hardware,the only external cable is the HDMI lead to the monitor.The BBB connects to the pinball controller pcb via 2 rows of 46pins .
If the Standard definition output is lifted to UHD no manufacturer of this type of board is going to design it with a processor that cant handle the output,the software is already emulated to run on the existing hardware.
There is too much scare mongering going on with this technology
The cheapest I have found so far for a BBB is $64 if people are worried about them lasting buy a spare buy 2 we all spend loads more than that on basic mods for our games anyway.