It depends on what you want to build. If you want to build impressive B2C software, this sounds like a recipe for disaster. I've worked with many backend engineers masquerading as full stack engineers who couldn't carbon copy a simple mockup design into a working UI if their life depended on it. Yet they never seem to notice how bad their implementation is, sometimes not even if you point it out to them even if the end users would notice; I think these engs are so enamored with their work they're in some kind of denial about the shortcomings. And that's just the visual parts. There's also skill required to take accessibility and conformance with web standards into account (HTML/CSS/JS stack is devious in that it lets you do things in ways that are "wrong"), which you can't easily fix later on by tweaking a bit here and there. So without this understanding, you end up with a crappy UI that's overengineered for what it is. Of course that all won't be an issue if you're building software you can sell even if the UI makes its users depressed.
Not saying your typical frontend engineer is flawless either. It's probably true that they're, on average, not as skilled sw architects as backend engineers, simply because a lot of their work focuses on details instead of architecting, and, again, the HTML/CSS/JS stack is incredibly flexible, in good and bad.
It's fair to point out that there is real skill involved in that kind of work. However, I don't trust the average "frontend developer" to do pixel perfect implementations either. Many of them don't even seem to know CSS anymore. And not to discount your experience, but being able to implement a design is something that is easily testable when evaluating candidates. Because I come from the multimedia agency world, most of the candidates I've hired were actually for that kind of role. Accidentally hiring people who can't do the work points to a competency issue with management. As I've pointed out elsewhere, I have the awards to speak authoritatively on this. But perhaps me focusing on average skill is just an unfair way to look it, since I'm never really looking for average anyways.
Not saying your typical frontend engineer is flawless either. It's probably true that they're, on average, not as skilled sw architects as backend engineers, simply because a lot of their work focuses on details instead of architecting, and, again, the HTML/CSS/JS stack is incredibly flexible, in good and bad.