I think there's a fundamental shift in the type of web-skills which are now in demand, due to a number of factors. Here's some things which come to mind:

- A "web designer" or "web developer" used to be a generalist who wrote HTML, CSS, and some jQuery. Now there's a demand for specialization: a UI/UX designer who can prototype, iterate quickly, and use real data if possible, and a UI/UX engineer who can develop large-scale apps with an eye towards security, performance, reusability, and maintainability.

- The need for the generalist web designer/developer seems supplanted by tools like Squarespace and Bootstrap, which make it easy to get acceptable results with fewer skills. It's the "commoditization of design".

- The need for specialized designers/engineers is spurred by a realization that good design can command a premium/competitive advantage (and that good design means iterating quickly and having a deep understanding of what makes fundamentally good UI and UX), and that the front-end benefits from sound engineering practices as much as the back-end, especially if you're building SPAs or large-scale apps with complex UXes.

- A lot of the design problems have been solved already. Questions such as when modals are appropriate, how to design forms effectively, what makes a good call-to-action, and how to structure IA effectively have been answered. Companies no longer need teams of people to work out answers to these questions, just one or two good leaders to evangelize the answers that are already established, and a team of UI engineers that can execute them well.