I hate this type of argument; it is very often nonsense. Sure, someone is not good because of its tools, but those enable him to be good it is not an either/or relation.
A lot of the time, some skills are indissociable from the necessary tooling, and it does not matter how good you are if you do not get the tool to enable it.
I had this argument with a friend about darts. I recently started playing with him and he has a lot more experience than I do, thus he is quite a bit better than me no matter what darts we use. But after we broke some darts, I decided to look at what the pro uses and buy something similar. He said the same thing about skills not requiring a particular dart.
Yet since we have had the new darts, we are both more consistent in our shots and hit the targets way more often, the consistency is extremely obvious considering how grouped the darts land compared to cheaper one.
I did not become magically better than he is, he still wins more often than I do. However, with those darts I improved a lot more than he did and if the end goal is proficiency, it seems logical to use as close the "end game" tooling as is reasonable for training.
Sometimes people feel like others are trying to minimize their achievements, but this is not about that at all. The tools are a major part of the road to expertise and anyone pretending otherwise is lying and I would be very suspicious. It reads like: "yeah I achieved my skill with this high level, performant tool, but just use this much worse one, it will be fine." I feel like it is disingenuous and most of the time, people trying to prevent new competitions in their fields.
And this is exactly why Apple's marketing is extremely deceptive at best. Sure, if you are an accomplished videographer and understand all the limitations coming from working with such a tool, you will work around/with those limitations, because you already know. But if you are starting out or still an amateur the iPhone is a poor choice as it will make your work harder than it would be with a more specialized camera (that can be had for cheaper than a brand-new iPhone, that most people do not need...).