Just read a short article and again, it showed how people think frontend is easy because it is not as complicated as low level system programming.
I think, the reason for this perception is because HTML/CSS is easy, readable, and anyone can start writing some HTML/CSS without spending days studying.
Not so for system programming where you have to understand multithreading, parallel programming, memory management, file system and more concepts.
I agree HTML/CSS is easy. Which is why I liked it, because programming shouldn't be difficult. Computers are supposed to make our live easier, not harder.
However, saying frontend development is easy because you know some HTML/CSS, is like saying you know how the body works because you know how the fingers move.
Frontend is complicated, especially with the responsive factor. Building a lean, responsive web requires a lot more than just googling and pasting code from w3schools.