Speaking from the perspective of one who has been on the PCT, (admittedly though did not finish - only 1700 miles). While on the trail, was accepted/ welcomed warmly/ was part of the "trail community" - some thoughts.
The trail itself is an ordeal...mentally and physically demanding. In my opinion the participants are generally divided into 3 types of hikers. Everyone soon enough finds themselves labeled by their trail actions and demeanor.
The first group is characterized just by their ability to put in the miles.
Hobbes wrote: The chief judgment of course being capable of actually hiking.
Starting at Campo, through the beginning desert sections, 25+ miles a day, (known as doing 20's or 30's) quickly separates you from those not capable of such agony. Those that can hike these miles (with a smile) generally gravitate toward each other. By the time you get to Tehachapi Pass, your acceptance (or not) into this "elite" group has pretty much been decided by your recent hiking style. You either can do it... or you are labeled as one who can't, and somewhat ostracized. All PCT hikers talk/ gossip about everything.
Hopscotching along, you continually encounter the same 200 - 300, like-minded individuals...agreed many (both men and women) are self-proclaimed a$$holes but all are generally accepted into this group just because they can hike the hike. By the time you hit Yosemite (~mile 942), everyone having made it this far without skipping are mostly accepted as a trail equals.
The second group consists of those not capable of consistently doing 20+ miles a day...(BTW, doing this many miles a day is necessary if you expect to finish the trail in a single season.) Many in group 2 will say that they are doing the PCT but are not generally accepted by group 1 due to their inability to put in the long miles, or they have a tendency to spend too much time partying at places like Hiker Heaven (mile 454), Casa De Luna (mile 474), or Hiker Town (mile 516).
Wandering Daisy wrote: I suspect that there is a lot more "drama" on the first 500 miles of the trail, than later, when 75% have dropped out.
The third group consists of those in Group 2 that readily skip major portions of the trail and hitch ahead to meet group 1 members further on up the PCT, (commonly known as yellow-lining), thinking that by being among these hikers they will be embraced...not so. Your actions (or lack of) on the trail will determine how accepted you will be among PCT peers.
BTW, proudly being a past PCT Group 1 alum - (just another dirt-bag a$$hole with attitude), I have been accepted out on the PCT tables in front of the Tuolumne Store, still part of the elite crowd. The hikers I've met there are astute and self-policing...calling out BS to those not accepted, and even though in the minority, the women of group 1 found there can be the cruelest and surprisingly, the most vocal.