I think the kinds of students that can afford good third-party advising very likely don't need it. Not only have they had facilitated access to experiences and broader academic services throughout their lifespan, but through the concerted effort of dozens of people, they are constantly having their story mirrored and reinforced.
Think about it this way: if your parents are oncologists and set up your shadowing, experiences, and research to be in that area, you're probably not going to wax poetic about emergency medicine. Everything is pre-ordained and organized for you from the very beginning, and so the struggle of getting to the application and having to integrate and synthesize something cohesive out of simply what was available is not a problem for you. You can probably get away with minor revision at your university's writing center.
In other words, of course it's easy to assume someone with this access may come across as too polished: this applicant already has their essay "written" their first day of college. It's more self-fulfilling prophecy than it is a retrospective reflection.
Conversely, the students who don't have the luxury of getting to take the scenic route struggle at pretty much every step and may come across as materially unprepared relative to the broader pool of applicants. It's like navigating an obstacle course blind.
A well-placed consultant could relay (at minimum) what the obstacle course looks like and perhaps even provide more personalized guidance if possible—but even that is unequal. Because if you spent your entire career advising people with unlimited resources, opportunities and stability to follow your instructions, you may find yourself confused on what to do with the applicant who has none.
Of course, we're talking about extremes on either side. The truth, statistically, is that many more applicants belong to the former extreme than the latter, though, and the shades of grey in between are still objectively resources not available to all applicants. I don't think we should even bother talking about legacies or donors.
This process is deeply unfair even before it ever starts. The haves receive copious, even ostentatious degrees of help to the point where all you need to be successful is a warm body... the have-nots are structurally gatekept and dissuaded from competing at all. It's so much more that plays into the perception of where one falls in the class hierarchy from the perspective of admissions than just whether or not you hired a consultant.
If you are lucky enough to have, it's hard to hide a Fulbright or Rhodes, no matter how rough and "unpolished" you may choose to write about it.
Ultimately, the struggle of "polish" is a lot of hand-waving nonsense that really just means your life has been so heavily managed that the writing and epistemic position of its narrator lacks a sense of responsibility and self-directed struggle/discovery. Like, it's giving NPC.
