I can imagine a few possible things that could have contributed.
First, being more open-minded when young and getting more close-minded as older is the usual way, not just for humans, but also for many animals. Kittens are more playful than adult cats. And “philosophy” is a way of playing with words and ideas, so naturally young people would play with different ideas (the smart ones with different smart-sounding ideas; the stupid ones with different simplistic ideas), and gradually settle on the One True Way of looking at things, as they stop being able to consider new ideas, and choose one of the known ones which seems to work best for them.
It makes sense from the “exploration / exploitation” point of view: When you have a lot of time ahead of you, and your opinions matter relatively little because you are in a relatively safe environment, it is good to explore and get new data. When time becomes scarce and potential mistakes costly, stick with the best of what you already know. Also, there is a trade-off between exploration and productivity; the time you spend playing with new ideas is the time you don’t spend earning money or working on your dreams; which is okay for a teenager with low value at job market. For an adult, job and/or children reduce the time and mental energy they can spend on thinking about things unrelated to immediate survival.
Second, people try to fit in their environment. I am sorry if this sounds too cynical, but the change of your friends probably reflects the change of the environment they are currently trying to fit in, where “scolding people, or snarky comments” are the standards of communication. (Trying to do anything else in such environment would probably gain you some snarky comments, and trying to reflect on the situation would get you scolded, plus some extra snarky comments. Not being sufficiently far-left of far-right would gain you low status as insufficiently “woke” or whatever is the right-wing equivalent.) Consider yourself lucky that you are not living in such environment.
Third, there is a possibility that a part of what you observe is simply you growing up. That not only the other people are changing, but also you start observing things that you didn’t notice before. I may be generalizing too much from my own example, but it was the case for me that the people whom I considered smart when I was a teenager, suddenly seem pretty stupid now. (Of course, the scary alternative is that this is just me achieving the One True Way of looking at things, unable to tolerate other views anymore.) For example, I used to be impressed by people who had “their own opinion” on theory of relativity or quantum physics. Then I learned something about these topics; and then I realized that most of what these people talk is pure bullshit, probably learned from a random pseudoscientific YouTube video. They still use the same strategy, and extend it to other topics; I am just not impressed by it anymore. Now that I have more information than I had as a teenager, I can see more ways how people can be wrong.
Also, if you formerly interracted with your friends in person, and now it’s mostly online, that too makes things worse.
I can imagine a few possible things that could have contributed.
First, being more open-minded when young and getting more close-minded as older is the usual way, not just for humans, but also for many animals. Kittens are more playful than adult cats. And “philosophy” is a way of playing with words and ideas, so naturally young people would play with different ideas (the smart ones with different smart-sounding ideas; the stupid ones with different simplistic ideas), and gradually settle on the One True Way of looking at things, as they stop being able to consider new ideas, and choose one of the known ones which seems to work best for them.
It makes sense from the “exploration / exploitation” point of view: When you have a lot of time ahead of you, and your opinions matter relatively little because you are in a relatively safe environment, it is good to explore and get new data. When time becomes scarce and potential mistakes costly, stick with the best of what you already know. Also, there is a trade-off between exploration and productivity; the time you spend playing with new ideas is the time you don’t spend earning money or working on your dreams; which is okay for a teenager with low value at job market. For an adult, job and/or children reduce the time and mental energy they can spend on thinking about things unrelated to immediate survival.
Second, people try to fit in their environment. I am sorry if this sounds too cynical, but the change of your friends probably reflects the change of the environment they are currently trying to fit in, where “scolding people, or snarky comments” are the standards of communication. (Trying to do anything else in such environment would probably gain you some snarky comments, and trying to reflect on the situation would get you scolded, plus some extra snarky comments. Not being sufficiently far-left of far-right would gain you low status as insufficiently “woke” or whatever is the right-wing equivalent.) Consider yourself lucky that you are not living in such environment.
Third, there is a possibility that a part of what you observe is simply you growing up. That not only the other people are changing, but also you start observing things that you didn’t notice before. I may be generalizing too much from my own example, but it was the case for me that the people whom I considered smart when I was a teenager, suddenly seem pretty stupid now. (Of course, the scary alternative is that this is just me achieving the One True Way of looking at things, unable to tolerate other views anymore.) For example, I used to be impressed by people who had “their own opinion” on theory of relativity or quantum physics. Then I learned something about these topics; and then I realized that most of what these people talk is pure bullshit, probably learned from a random pseudoscientific YouTube video. They still use the same strategy, and extend it to other topics; I am just not impressed by it anymore. Now that I have more information than I had as a teenager, I can see more ways how people can be wrong.
Also, if you formerly interracted with your friends in person, and now it’s mostly online, that too makes things worse.