We could similarly restrict all food production to rice and people would get used to it and even enjoy it, but that doesn't mean it is a solution towards a more diverse diet.
You are fundamentally talking about increasing diversity in one area by reducing choice in another. Isn't that antithetical?
Regarding food vs jobs, I think it's not a very good analogy because
a) almost every job has a lot to it that could be interesting for anyone
We are not limiting all jobs to "Wordpress site template maintainer for small e-commerce sites" or "MySQL DB engineer specializing in scaling and indexing databases with mostly JSON-based tables". If you are a front-end web dev, you could choose to end up specializing in front-end driven analytics or SVG drawing or something higher-level like d3 plotting or anything in HTML5 games or photoshop-to-code conversion or migrate to photoshop-based design etc etc
B) The goal is not to maximize diversity of food or diversity of jobs. I am not implying avoiding increasing specialization.
You are fundamentally talking about increasing diversity in one area by reducing choice in another. Isn't that antithetical?
edit: your edit makes more sense :)