Is this an example of cancel culture?

I found and article that talks about a Michigan teacher that was recently fired because he tweeted that Donald Trump is the president. The school district denies he was fired for the tweet, but they will not comment on why he was fired. He was a popular teacher, known to be apolitical and did not bring it into the classroom. So why fire him? Another article shows that other teachers not only tweeted bad things about Trump but also urged students to read anti-Trump articles and no disciplinary action was taken. Does this look like censorship or cancel culture?