It is easy to write shitty code as a web developer and get something to work, however unmaintainably and unprofessionally. That doesn't make it any easier to write excellent, clean, and extensible code. In fact, it makes it harder because you're more likely to find yourself in an organization which has been able to survive without being able to write clean and professional code.

Branching out into other domains can give you insights if you find them interesting, but if you do in fact care about web development, focus on taking pride in what you build as a web developer.