Could have been been annoyed at his confidence level not matching his accuracy level.
Everyone thinks speaking up is helpful, but being confident when wrong isn't. Could have spoken up with a humble concern, or been confident they're incompetent and didn't de-ice correctly.
Usually how you speak is as important as what you say.

Agreed. If you genuinely have a concern, don’t hold back.

Moving on......

TOTD

Any pilot who thinks going above and beyond to help a coworker degrades the profession or damages the profession’s image. To the contrary, exhibiting humility and a servant spirit will elicit respect from others.

“Leadership is an opportunity to serve. It is not a trumpet call to self–importance.”

–Donald Walters

Any chance you could get this quote into the hand’s of Kim Jong Un’s buddy, Dim Dumb Don?

Shhhh! You’re gonna trigger 3/4ths of the people here

hmmm...only 3/4?

Boom...filler

Trying to justify why you cross seatbelts?

Did you just out yourself? 😊

But seriously, wouldn’t the profession benefit from being widely recognized as having these attributes? Many pilots are strong leaders who carry themselves with humility and compassion. But a small, vocal faction who means well but mistakenly thinks they are helping our cause can tarnish the reputation of the entire group and do more damage than good.