To be fair, “I did my own research” is not an argument, and should be considered unconvincing. It’s a claim, an unsubstantiated claim.
A meaningful answer would produce an argument informed by that research, how they disagree, and why.
As a side effect, this proves they did their research, although that part is entirely irrelevant. It allows to clear up misunderstandings, in case they missed important parts while doing their research. Some crucial insights aren’t that obvious.
Most importantly, making an argument informed by your own research contributes constructively to the discussion and advances it.