In fact, we should be able to build ovens that last a lifetime. And not only ovens, there are many appliances and gear that can easily be made to last a lifetime, except for some wearing parts. However, many companies that did this were competed to bankruptcy by cheap low quality competing products.
With the abundance of low(er) quality products, we tend to expect a shorter lifetime.
Luckily there are still a few countries at the bottom of the world with good consumer legislation.
But that price increase will go into longer-lasting parts, because that costs a lot less than needing to replace every unit halfway through the warranty period.
And since the 20 year oven is a lot cheaper to build than two 10 year ovens, the per-year price to the consumer will go down.
The only exception is when people buy from a foreign retailer online. However that is a problem regardless of where the retailer is as long as they are not in your country. My daughter (in the UK) currently has a problem with Boox (in the EU) refusing to replace a product that was delivered with a faulty screen claiming that she must have damaged it.
Who knows, maybe the author has been using the oven excessively or never cleaned it etc.
So far, we‘ve heard one side only.
That's actually false. Almost all of the engineered goods are engineered to a certain lifetime. Usually companies have internal endurance testing results for every item. The ones who care about will release their expectations.
Considering the cost of sending a lawyer attend the hearing and the potential risk of creating a precedent, it may simpler and cheaper to send an engineer when someone complains too loudly...
If they got invited to a hundred cases at the same time, they'd send a lawyer and perhaps even would tweak the design to include some extra $1 parts which actually work.