@cephie I think so - to try and rephrase it in the context of your description, my argument is that "making an environment that suits me in a personal way" would not be such a common requirement if desktop environments actually did a good job of being suitable for a lot of people's needs, but they don't really. And so this is a thing that people end up trying to solve themselves.
And I think that at the root of this is not just "the existing desktop environments don't suit common needs", but also "I do not *trust* that they will, now or in the future" - which is something I feel I also see in your comment about "ever-shrinking customisability"; it speaks of a concern that things will get worse, instead of better.
And I think that applies to a lot of people, and that it would be much less of an issue if desktop environments provided a better experience that suits more people's needs out-of-the-box, and builds their trust better.
This - sometimes bordering on aggressive - drive for total customization in the Linux userbase is, to me, simply a symptom that people's needs are not being met.