Since the fact that mechanical timers have been known to last for decades without failures, it makes sense that the initial added cost involved would tend to please customers by insuring long-term reliability.
On the other hand, electronic control boards are more prone to failures, things like aging capacitors, resistors going out of tolerance, and relay contacts pitting, solder connections failing, means that questional durability, along with an expensive visit from a service tech is not something a customer wants to worry about.
You said yourself that the older-designs of refrigerators are more worthy than the new expensive ones.
And those older fridges didn't use electronics in them.
So your post #67 above sounds contradictory.
The issue is that the market has placed cost above all else. You and I can say, on the internet, we care about reliability (and we certainly do), but in the real world, where appliances get sold at stores like mine and Combo52's.... People look at price + features far quicker than they ever look at electromechanical controls, or look for Consumer Reports guides on reliability.
I will have a much easier time selling a Samsung topload washer than a Speed Queen because one is $500 and the other is $1300.
So no, I am not being contradictory. I am explaining that long-lasting electromechanical controls cost more money than electronic ones. They last longer without question, but at significantly higher costs.
In the eye of consumers, paying 2x the cost for 2x the lifespan is often not a key part of purchasing an appliance at this time. I wish it wasn't because economies of scale could likely reduce the 2x/2x paradigm we see with Speed Queens, but its been difficult the past ~35 years to convince people to pay 20-30% more for a far more stout appliance. Maytag realized that and found out the really painful way in the 1980s-1990s with buying out Magic Chef and then labeling the Norge machine as a Maytag Performa at a much lower price.... In their eyes they "had" to cheapen the product to compete.
In regards to Pierre's comment, I would say that depends on model. If it was a GE, I'd use a SmartHQ and see why it wasn't trigger hot water to see why the encoder or whatever is sending the hot signal isn't triggering. One general advantage with boards should be (but often is not due to manufacturer stupidity or gating) is far easier diagnosis, which is slowly happening.
I would also note on control boards - longevity is priced into the board. They intentionally only build the boards to last 5, 7, or 10 years. Relays are not a stoic piece of equipment. If they were, the military/DOE would only use electromechanical systems, but they don't. Mike Carlson did a "Thunderdome" test years' back on PCBs and showed that typical relay lifespans in, say, a Whirlpool Duet dryer were built to last 20,000 - 30,000 cycles with an Omron relay. Inversely, upgrading that relay (which fails at 10 years usually) could be upgraded to a TE Connectivity relay which would push that specific module/failure to 100,000 cycles, or a 25-30 year duty cycle.
So even then, PCBs aren't even the real enemy: Cheap designs are.