Throughout my professional life, and especially within the LE field, I can say that I have seen the "ok boomer" concept manifest into frustration, and not just for myself. When I first got into LE, nearly every senior officer or supervisor I came into contact with on duty was old enough to be parent. This had a really weird way of creating how things worked out through my shift. The main issue, at least for me, was that there was a lot of "this is how it's always been done" type dogma going on, and those who would make those statements almost always did so when it would directly pertain to something that would benefiting them. I found that when it would benefit the younger (or next) generation of LEO's coming up through the ranks, the rules would change arbitrarily to stop it or would be designed in such a way that it would still benefit the older officers in some way. It would be easy to see this as an issue exclusive to LE, but yet it isn't. I have seen it in the private sector before I got into LE, almost identical in nature.
After the issues with dogma come the second biggest issue I have seen when considering the generational divide. The older officers, especially those in Gen X (or older as they are sort of the same in mindset) took new ideas, approaches and competency as a direct assault against themselves. They took it very personal. One such example of this I have is when a performance evaluation was due and I was leading my area in a particular field of activity, once certain older officers found out and one specifically found out this was true by the numbers, he actually confronted me and told me to "chill the fuck out, you are making everyone else look bad." This happened about ten, or so, ago and that officer has since retired, but it was a very eye opening moment for me. I am being called out for doing my job better, or more effectively, than a senior officer and for that I am wrong? I guess that's part of the separation beyond the generations. I let my work speak for itself whereas the senior officers believed they were entitled to certain accolades for simply being on the job for as long as they were. While they may deserve certain considerations, those which they were after they had not earned and I did through hard work.
Even still, I will always strive to not allow myself to look upon a person and make a judgement of their ability based on their age. That is not the correct way to go about determining how competent or capable a person is. There are plenty examples of older, senior, officers who are still vastly most capable that any younger officer and the opposite is also true. Using labels such as boomer, zoomer or millennial should be done at your discretion and seldom negatively. Let a persons actions determine the label you give them, not their age.