It's a matter of money and career perspective. Being a good software developer requires a lot of learning. The job can be quite stressful and your knowledge devalues continuously because of tech change.
In the long run other professions probably are more attractive, don't require permanent re-learning and at least provide an option to climb up a career+$ ladder.
Provide better pay & conditions and you'll see more engineers.
pointless. Its the number of objects not the size of primitive fields (e.g. the char array) which hurts GC and consumes memory. This proposal will save <10% on an average short string instance but probably waste performance.