This is a fair concern of style recommenders in general. Yes, we want to shape text. And what follows is merely a partial response, but it should address some of your concerns.
First, much of the advice is that certain word sequences are problematic without suggesting any particular replacement text. There are a few reasons for this (including the computational natures of error-detection vs. solution-recommendation problems). The reason most relevant to your concern is that solution-recommendations are more likely to produce a homogenizing effect because they have a driving effect, wherein using a particular set of words is deemed superior to another set of words. Much in the way that the diversity of life-forms has arisen because of selective pressures, by eliminating the least fit combinations of words, the native variation in writing can flourish all the more readily.
The goal is not to homogenize text for the sake of uniformity, but rather to identify those cases that have been identified by respected authors and usage guides as being specifically problematic. Any text that is sufficiently artful and compelling to have not been specifically addressed by these sources should not be able to be caught by the linter. Novelty will continue to introduce new usages, and some of them will be poor. Authors identified as trustworthy may point these out, but this will only be in retrospect. If you do not trust a guide's point of view, our strongest recommendation would be to turn off the modules associated with that guide. You can see some of the module names and a high-level description here: http://proselint.com/checks/.
Finally, I will modify a quote in the Foreword[^fn2] by Robert Bringhurst in The Elements of Typographic Style (version 3.2, 2004)
> [Language usage] thrives as a shared concern — and there are no paths at all where there are no shared desires and directions. A [language user] determined to forge new routes must move, like other solitary travelers, through uninhabited country and against the grain of the land, crossing common thoroughfares in the silence before dawn. The subject [of proselint] is not [stylistic] solitude, but the old, well-traveled roads at the core of the tradition: paths that each of us is free to follow or not, and to enter and leave when we choose — if only we know the paths are there and have a sense of where the lead. That freedom is denied us if the tradition is concealed or left for dead. Originality is everywhere, but much originality is blocked if the way back to earlier discoveries is cut or overgrown.
[^fn2]: Only because we are on the topic of historical traditions and stylistic guides, it should be mentioned that a foreword – according to book design tradition – would be written by an individual other than the author about the author, the book, and usually the relation between them. In this case, the section in Bringhurst's masterpiece labeled "Foreword" would likely be better described as "Preface" or "Introduction". Given his knowledge of book design, I shall assume that this was a conscious departure from the road of tradition, even if I cannot appreciate the new view that it offers.