TL;DR: read this first:
https://slate.com/news-and-politics/2019/05/sexual-assault-r...--------------------------------------
You are asking the wrong question.
The judges don't give reasons for their sentences like that (i.e., the judge is under no obligation to say "I was going to give this person X years, but I'm giving them X-Y because the victim was wearing a mini skirt").
The question you should be asking is: is victim's clothing an admissible evidence in rape cases? That's to say, is it something that the defense uses in their arguments?
And the answer is that, historically, yes, victim's clothing has been extensively used by the defense in rape cases.[1]
The issue was serious enough that states started to adopt laws that banned using clothing as indication of consent in rape cases. By 1994, NY introduced such a law - being the second state in the nation to do so[2].
However, no matter what the law is regarding admissible evidence, the judges will most likely know what the victim was wearing because that, in itself, is collected for evidence. To argue that this does not factor into sentencing would be improbable given the prevalent attitudes in our society, and studies like[5] confirm that.
Which brings us to the main problem: that even without taking clothing as an excuse, sexual assault perpetrators are often left unpunished or given a slap on the wrist, like in the infamous case of the rapist Brock Turner[7].
This is, of course, tangential to the point that a significant part of the population believes that clothing can be an indicator of consent [3][4], which results in the dismal proportion of cases being reported to begin with, and then a small percentage of those brought to prosecution.
In the end, the judges simple don't give prison time to rapists. The judges give light sentences citing anything as a reason, without consequence.
You can see plenty of cases in the survey[8], many of them quite recent.
The analysis of the extent to which victim-blaming has been a factor in each of those cases is left as an exercise to the reader.
[1]https://scholarship.law.umn.edu/cgi/viewcontent.cgi?article=...
[2]https://www.nytimes.com/1994/07/30/nyregion/new-law-says-vic...
[3]https://www.washingtonpost.com/posteverything/wp/2016/04/13/...
[4]https://philpapers.org/archive/WOLPDA-3.pdf
[5]https://escholarship.org/content/qt0fq160dv/qt0fq160dv.pdf?t...
[7]https://www.nytimes.com/2016/06/09/us/brock-turner-blamed-dr...
[8]https://slate.com/news-and-politics/2019/05/sexual-assault-r...