Wikipedia is not a reliable source and turns out your high school teacher was not an out of touch boomer. Many people are still under the impression that everything there is factual and unbiased, when in reality, it's actually the opposite.
It gets some things right, but it's also extremely inaccurate at times and highly susceptible to vandalism. Not only that, but PR companies, advertisers, political parties and even religious groups constantly edit articles with misleading information that either paints them in a positive light, or makes the other side/detractors look bad in the eyes of the reader.
Even Larry Sagner, wikipedia's co-founder and they guy who gave it it's name, has been very vocal about his criticism of the website. He's been very critical about many of its issues, including the website's neutral point of view that has mostly been abandoned, he recently he wrote an article about the blatant and extreme left bias on some articles and topics, which is a really interesting read.