I do not want to nit picking our discussion. But I seem failed to convey my ideas:
1. QA exists prevalently
2. In general software companies do not have dedicated QA team for every engineer team
3. Lack of testing is a real concern for maintainability in big companies, because developers need to write tests themselves.
I do not disagree with your examples, but they are orthogonal to my point #2 #3. Let's go back to your original comment:
"""
The thing is, most large companies have a QA team so this fear is not super tangible to many developers. And small startups are more focused on building stuff quickly (which they should be).
"""
The comment was responding to:
"""
Once you release a product that will be used by many customers and developed by many people throughout its lifecycle, which come and go as the time passes, you won't be able to maintain/extend it without a proper testing suite. It's not only about complexity, but also about maintainability. Some tests will also rot in time.
"""
My understanding is that, you meant to say that the fear of lack of testing harms maintainability is not so relevant to developers in big companies, because they have dedicated QA team (writ tests for them).
My comment says, in general, big companies do not have dedicated QA teams for dev teams, so there is no dedicated QA team write tests for dev team. My examples are 2 of the largest software companies in the world. Among them, Google redefined how people access information, Amazon reinvented how developers access computing resources.
I think my examples support my intention to prove that your statement and what it implied, in general, is not true.
