Oh I've been around a long time too, and I've definitely had that experience in the past. Presentation logic was the really _big_ one years ago. Few devs seemed at all bothered if their views were extremely complex, contained heavily nested conditionals, poorly componentised, etc. Presentation wasn't seen as "serious" code, because real devs did backends. As a result, so much of our available tools, libraries, docs, blog posts, etc. were valued based on how quickly you can churn out something that matches some mockup at one point in time, and that's it. You'd never make any significant updates, only create new pages to replace it. In this world, a completely separate dev (or designer) would throw together the HTML/CSS and the ecma dev would link up some events to the buttons.
I've really seen it flip after React matured, and everyone started transpiling w/ bundlers. I don't have some `colors.scss` with a bunch of constants, and then redefine those same constants in my .js anywhere -- I have a .js file with my palette. I don't embed logic into the template with a bunch of `<div ng-if` stuff anymore, I can use the same `if` I use everywhere else. All my static analysis for unreachable code detection, style guides, etc. runs the same everywhere.
I'd argue that those "simpler js enhanced pages" aren't so much simpler, as they are merely more familiar. 1 consistent approach in one language, that is equally (or more) suited for declarative code, is simpler than 3 languages with 3 approaches. One module that says `export default css({ p: { fontSize: '16px' } });` then importing it into another file is simpler than some scss `.MyBigClassName { p { font-size: 16px; } }` then remembering that classname in your HTML. `h('p', { onClick }, 'Hello!')` (or `<p onClick={onClick}>Hello</p>` in jsx) isn't more complicated than `<p class="foobar">Hello</p>` and some js elsewhere that says `$('.foobar').click(` or whatever.
I've taken this approach with my very intern/jr heavy team, and they all take to it really fast. It tends to be the older devs who are more resistant, because it requires changing old habits.