What are some of the Unconvincing phrases people think are convincing

Not particular arguments or fonts there of, like not "Goku is 11.5D" or "anyone who argues anyone is faster than light", but instead general phrases people use to seemingly try to convince you of a point, and it only does the opposite.

Some examples for me include

• "Haven't we been over this" *mentions an outdated forum post neither of us posted on*
• "Believe what you want, no one else thinks X"