I totally agree with what you are saying. I did a little digging on that website and came up with a picture of the author Jon Hoff and as both you and I suspected, he is young. You could tell just by the way the article was written. This is a young person on the voyage of discovery. Someone who is a Bernie Sanders supporter but who has an open mind.
I can see by your name that you have probably also made a similar journey. As for myself, when I was young, I was an idealist so naturally I was a little more left of center. Yes, I voted for Ronald Reagan, but at the same time I also was interested in what Lyndon Larouche had to say. As a young person, the ideas of ending world hunger and poverty appealed to me as it usually does with everyone who is of a high mind. However, as the years go on, if we are honest with ourselves, we come to realize the pack of lies that socialism/communism sells. I would be disappointed in a young man who undergoes a complete change after one Donald Trump meeting. In my opinion, he took away the right lesson. Trump is not the be-all/end-all to classical liberalism but his followers are intrinsically. A seed was planted. I would not be surprised if in five years or less this guy is on our side....
I have. I was raised in a very liberal environment, with my head filled with what I call "poverty culture" (which is very liberal). My voyage towards enlightenment took a long time, step by tiny step. I never registered Democrat, but I voted that way. I cast my first vote for Carter when he lost to Reagan. I remember all the fear-mongering from the media over Reagan, and I believed it, at first--until it occurred to me that the plethora of horrible things they predicted never came to pass. The little things kept piling up, until the Democrat party nominated Bill Clinton--and that was the death-blow to my early liberal indoctrination. I've voted Republican ever since.
In order to make such a journey, one must be open minded. Sadly, that quality is fairly rare.