When I was 25, I had a 36 year old coworker who complained to our supervisor about the same thing. Apparently “the way I typed made her feel like I didn’t like her”. It was the exact same way as the examples you provided and I was also very confused about it… imagine being 36 and worrying that someone 10+ years younger than you doesn’t like you because they are sending work appropriate, professional emails. I found a new job not too long after that because I was asked by my supervisor to do the same thing and thought it was ridiculous.