In a less capital-intensive industry, you'd see small competitors building higher quality goods for a premium price. You see this in, for instance, leather goods (where you can get very high quality leather wallets for under $100), clothing (much better goods available online for only slightly more than mass-market retail), etc. Small competitors don't care about planned obsolesence when they could only dream about capturing enough market share where planned obsolesence becomes necessary to keep profits growing every year.

But the capital barriers to entry for new cars and smartphones are way too high. Elon and Tesla were the last true upstart to even come close to a semi-affordable premium option, and they burned through billions in startup capital to get there.

If the government can't reduce the barriers to entry for Smith's Invisible Hand to naturally produce competitors, then the government needs to regulate the natural oligopoly.