[nsotelo]

Nothing is absolute, of course if you take it far enough the seams of the argument tear but there is merit to it.

A senior browser frontend developer is likely to pick up mobile development quite quickly.

Likewise someone who's been doing Spring Boot Java backends for years and is proficient with databases, caching, etc. Isn't necessarily going to find it hard to switch to a serverless nodejs paradigm.

The network card person is probably able to handle the embedded microwave oven.

Etc.

[drdaeman]

I believe it's not about learning how to do things. That's not that hard. It's about knowing about the gotchas - things not to do. Every technology stack has its warts and oddities.

It's not that hard to write some code that would do the job, it's hard and cost prohibitive to realize all the initially hidden nuances that might require redesign because of shortsightedness of the original one.

Requires either a really bright fast-thinking mind or just a lot of experience making one's fair share of mistakes. There are geniuses out there who can make perfect models in their heads, but I believe a lot of people just scrape by knowing where them or others had shot themselves in the foot before. And such experience only comes with time.