Planned obsolescence is something the manufacturer creates because the consumer wants it. The driving factor is price and the public usually accepts a cheaper alternative.
Let me give you an example. Our eight old dining table chairs were in need of new seat padding after almost 20 years of good use. The timber is excellent and they were manufactured at Melchair Pty Ltd Melbourne in 1995. My wife phoned around for some quotes and the price for refurbishing ranged from $1000 to $3000 for eight chairs! Now, we could have bought a brand new table and 8 chairs made in China for less than the lowest quote.
I said no way Jose to all of this and spent this weekend refurbishing the chairs myself. Bought the best padding at Clark rubber and the chairs are ready for the next 20 years. Total outlay was $100 and 2 sore hands and wrists.
Fortunately, you can do this sort of repair on good old products if they are taken care of. Unfortunately today, too many products are built to a price and are only good while they last. In many cases, the consumer will change the product before it dies. This is what 90% of the people want and the drivers are price and style.