I still do something similar within a vendor today and I do find myself having to consciously tell myself "It's OK not to understand much about $X technology area."
There are still roles that probably do require actually specializing to become great at (e.g. graphics/game engine dev comes to mind) but those roles are comparably rare. Most of the Android/iOS/Java/C#/React/JS/TypeScript/etc developers I’ve met could become proficient in any of those other technologies, they just choose not to, perhaps out of comfort. FWIW, in my personal experience, willingness to learn new things/broaden perspective & skill base (a.k.a. being a generalist) is correlated with job performance to the point where ‘not in my job description’ and ‘no I won’t learn UIKit, I’m an Android developer’ stand out as major red flags. “I don’t have time to learn React because I need to familiarize myself with the 8 new types of pointers C++ added this release’ feels a little more reasonable, but again, the great C++ developers I’ve met are still willing to get their hands dirty in other areas.
Tl;dr specialists are (usually) generalists with an attitude problem
(In this case better job means: fixes it the first time, with no new problems after, and the work doesn't feel sloppy unlike the warranty repair I had to have done by the dealer. In the later case they just reattached 2 panels wrong, something a specialist should be able to do without problems)