Most things related to etiquette have changed; essentially there is none. There are plenty of rules, but things related to common courtesy have become foreign to most, or optional at best. Still, I try to stick with shared trail etiquette, regardless, and try to adapt to the reactions or avoid them. I'm never in a hurry anymore, so I tend to hang back and look for opportunities to pass, sometimes at a road crossing or slowly when people naturally/randomly/accidentally move to the side while staring at their smart phones, and using a very light touch on my bell. On trails, I follow the hierarchy, horses at the top, walkers next, and bikes last. The old heels (and hooves) before wheels, with respect to right of way, and yield to everyone going uphill, when descending. The bell is a courtesy, but doesn't establish a right or right of way, or right to pass; just a signal that you're about to take the opportunity to pass.
Way back when I was in school, I took a part time job as a banquette waiter. I had to learn a lot of rules and etiquette, related to serving, as well as dining. We never removed plates from the table if there was still someone finishing theirs, unless asked specifically, since those diners should never feel rushed. That's not the case today, except in very high end restaurants, and waiters are taught to bus plates as soon as someone finishes, partly for turnover, and partly so a person "doesn't have an empty plate in front of them". I eat faster than my wife, so I'm often sitting with one small bite on my fork, so the waiter doesn't bus it and make my wife feel rushed. My wife notices and happy. Who would have thought that just following etiquette could be viewed as chivalry, lol.
I also did VIP service a few times, where there was a waiter for each two guests at the table, so 6 waiters for a table of 12. Everything was synchronized, bringing plates to the table, and removing them. There were always a few diners that didn't know the etiquette, and we would follow our first rule of never letting the customer feel uneasy or embarrassed. For one meal, there were some appetizers that people ate with their hands/fingers. Following that, we'd bring silver finger bowls to the table, which had warm water and a lemon slice for the fragrance. We also brought a plate with a small rolled up washcloth on it. The diners used these to wash then dry their hands before the next course. One of the ladies I was serving was not familiar with this, and proceeded to drink her "lemon soup". I couldn't say anything, because of the number one rule, but she finally figured it out when she looked around. The folks yelling on the trail don't really understand the etiquette and the courtesy you are providing them. They are basically the lemon soup diners. All you really can do is stick with being courteous.
Of course, there are some obnoxious bike riders out there too. Yesterday I as riding my stand up scooter, and there was a guy on another scooter riding pretty slowly, drifting left and right. I just slowed down to wait for my opportunity to pass, when a bike rider came up yelling "bike coming, bike coming" over and over (and over). I was already fully to the right, but he kept it up and finally passed. We both exited the trail at the same place, to ride up a surface street, with a 7% grade. My scooter climbs that at 21mph in the lowest setting, so it sort of felt good, yelling "scooter coming" while whizzing by him. That courtesy felt so much better than using my bell.
