That's often true, but once in a while there can be some more complicated clientside programming too, like working with charts, visualizations, maps, graphics,

That's often true, but once in a while there can be some more complicated clientside programming too, like working with charts, visualizations, maps, graphics, Canvas or SVG manipulation, etc. The frontend these days can basically be its own platform (not that it necessarily SHOULD, but could). Especially if you end up farming out processor-intensive stuff to WASM/WebGL/WebGPU. And even the basic web app functionality isn't necessarily intuitive. No, it's not classical programming like algorithms and data structures... maybe something more like dev-ops or networking? Things like CORS, different caches (memory/disk/CDN/KV/framework/etc), out-of-order parallel async, web workers, push events (SSEs, websockets), HTTPS, DNS, gzip/brotli, and all that sort of stuff. It's no fun to deal with, completely invisible to users, but still typically part of our jobs and very different from the design & layout side of things.