There's a heated debate between car enthusiasts whether modern car electronics limits the lifespan of cars after 1980. Bosch announced the CAN bus in 1983 and produced it from 1987 onwards. Since then many different vehicle bus systems have been standardized and implanted into cars. With the bus the previously independent components (i.e. ABS, engine electronics, traction control, etc.) are connected and need to cooperate to make the car work properly. Therefore cars became much more complex as a system. There was of course electronics in cars before the introduction of bus systems, i.e. in the electronic fuel injection (e.g. Bosch L-Jetronic and others), starting in the late sixties and popular in the 70ies and 80ies. But these components were still fairly restricted and in many case can be replaced with simpler systems should there be a lack of spare parts. The problem with "modern" electronics is threefold:
a) Electronic components age and stop to work when connections corrode or individual parts defect.
b) Many manufacturers have disappeared, and even if the manufacturer still exists then there are no spare parts available because the lifetime of many of these components was so short
c) To analyze and diagnose problems you need the right technical equipment and specialist engineers. Often neither this equipment nor the specialists are available.
An interesting example for these problems was recently given by Mario Theissen (former BMW formula 1 team lead) in Auto Motor und Sport. "We once had a Brabham-BMW in Goodwood (must have been in the 80ies, comment from the editor). It took us all the experts of our house to make it run. The problem is electronics. You need to keep the components well maintained as there are no application systems and components available anymore today." Apparently BMW is thinking about building a more modern engine control technology that can be adapted to older racing cars from different time periods to solve the problem.
And this probably will be the solution also for other cars, such as the sports cars and GTs of the 80ies and 90ies to preserve them for the future. There will be a business building such an adaptable and configurable bus system and control electronics. And there will be computer development and tuning environments to configure these systems and even optimize them to be more fuel efficient and environmentally improved. Car owners maybe will have to spend 3'000 or 8'000 Euros to adapt their car, but that's little money if they can continue to use their loved future classic for another 5 or 10 years and create the base for value enhancement over the years.
Two additional thoughts.
What really helps of course is the fact that modern microprocessors are much more powerful than the technology from years ago. With this it will be easily possible to emulate and simulate what has been before.
From a business point of view the effort of reengineering ancient electronics is more viable the larger the volume of cars you can equip. This sort of goes against the notion that the more exclusive a car is the more expensive it can become as a classic. So there will be some trade off here.
But the chances are good that you can continue to drive your BMW M3 E30 until it's a true classic. Let's keep our fingers crossed!