Simple bikes are simple to maintain and repair, and they don't "argue" with the rider if some simple sensor tells the bike that something is not optimal. Still, I think there is an over driven fear of electronics. Further, the electronics do not only provide improved performance and fuel economy, but it also reduces service intervals and improves the longevity and reliability of the bike, and in many instances makes fault finding child's play... if you have the diagnostic tools, don't approach electronics like it was voodoo, and think of electronic parts as any other part which can be replaced.
For the Dakar, a diagnostic tool is not very expensive:
The Home of GS-911 — HEX Code and using it is easy and can save a novice mechanic hours of fault searching. Even if an OEM sensor or relay should no longer be available in the market place, there are options from other bikes. Should the brains of the bike go up in smoke, and OEM parts are no longer available, then you should be able to find a provider who has mapped the software and can provide an aftermarket part that does not only work, but that probably works better than the original. There are options such as booster plugs, etc, for the Dakar which takes reliability and smoother performance to a whole other level. As long as there are many specimens of the bike in the market place, there will always exist parts... like any other non-electronic bikes. And, even if the bike should turn into a rear classic, then there will be companies out there that can custom make most of what you need.
Electronic parts can be carried as a spare like any other spare.
My general opinion is that newer bikes are better than older bikes in just about every aspect except for complexity... the very complexity that makes the rest so much better. I love turning my wrench on my 50 year old bikes, but fret not doing the same to my Dakar... it is all about ones mindset.
Still, it is also my general opinion that there are more incompetent "professional" mechanics out there than competent ones. Any overlander should get to know their bike inside and carry out all their own services and repairs. It may be a bit scary and difficult the first few times, and take ages with much disruptive research. The learning curve might be steep... but not very long... you only have to learn your own bike. For me, even washing the bike is a ritual done thoroughly inside and out by sponge and brush... it allows me to inspect every bolt, learn every part, and get to know the bike and fix things early before they become a serious problem to contend with. I'm by no means an expert and have found that I'm able to sort out things where the mechanics at certified dealers have given up. The f650.com community has far more knowledge than any single mechanic, and it is all available at your fingertips.