I think it’s more related to “tribes” than anything else. A great designer that can do passable js is going to be more valuable to a company on the front end, a

I think it’s more related to “tribes” than anything else. A great designer that can do passable js is going to be more valuable to a company on the front end, and a great dev that does quality work that will last for 5 years without refactoring is more valuable to a company on the backend, while a great “full stack” engineer is more valuable to the company helping multiple teams in a DevOps role. Not to mention that those folks will naturally gravitate towards those distinct roles. Over time, the frontend design types will want more control over what they can and can’t do userland, and nobody else gives a damn because it doesn’t affect their day-to-day and in many cases makes their codebase cleaner / more “pure” because UI concerns get really messy for a variety of reasons. It also generally feels safest to a company to put junior programmers on the frontend where even if they mess something up, at least the whole underlying system won’t be hosed. That allows juniors and mids to build chops more rapidly. Anyway that’s all just my anecdata / speculation.