Yet, I don't see the issue in the OP. This was environmental, and it doesn't make claims to the bigger pictures. That is, the description was about the situation and the way it made him feel... and those feelings are legitimate. The language communicated his impressions of it. Now maybe those impressions should be expressed in a different language, but then we wouldn't of been able to understand how he really felt in that moment.
In addition, the statements made were of the "these (x) are (y)", as in "these groups had traits that are associated to ESTP", not "all (y) are (x)", as in "all ESTPs have these traits". The difference is important in stereotyping.
Even though Sub may disagree, I haven't seen a better answer than an insecurity trigger brought up on by some shadow of his personality reflected in the local culture he intruded on. Because he described it as ESTP, I assume it is really the rough and tumble approach, which has a great deal of social context and belonging. I don't see anything personal in his post, or anything about others. From the start I read it as him trying to understand his own insecurity.
So, IMO, this was more of a projection of the general MBTI issue between S/N rather than something specific Sub brought up. And I find it unfortunate that it means that the Ns that do care have to spend a great deal of mental energy as to not rile up this reaction, while it is really perpetuated by others directly who simply don't care and would even go out of their way to enforce that stereotype.
Things have gotten better, overall, looking at the long run. It just takes coming down on the cultural aspect, gaining diversity and so forth. I was reading my old posts from a year ago and the direct S bias was pretty impressive back then. It comes down to the same thing as it did then - finding those that perpetuate it, calling them down on it, having lots of people come down on them, etc. But it really doesn't help when threads like this get the hammer, IMO.