Before the epoch of the smartphone, things like innovation were used to describe more than just a spec bump. While some complaints about the current market may be nitpicky, others are genuinely concerning and need attention.
https://www.notebookcheck.net/Stale-smartphones-4-moribund-mobile-trends-that-need-to-go.609768.0.html
1- At that time companies are trying to find what works, now they are only polishing what they already know.
2- Sometimes an easy repairable product can cost way more, but it's true some companies make it difficult on purpose, many customer don't care though.
3- Glass is not the best solution, but it is what works right now with 4G/5G Antennas, people don't like plastic, and other materials like ceramic costs way more.