If the interviewer is a good interviewer - they inadvertently gave the candidate an oportunity to demonstrate a range of skills.
An outstanding candidate when questioned would mention that in most languages this evalates to that, but in python it evaluates to this, and offer an alternate method chaining and's on the spot in response to the confustion.
If they are a bad interviewer - they would allow their ego to derail the interview.
An outstanding candidate might be an average candidate in a wrong setting.
With my last job, I fumbled an easy question for me that I usually wouldn't, but it was a 10pm interview after I got up at 4am that morning and have almost fallen asleep when putting my kids to sleep at 9pm. I got the job (and then got promoted twice in 18 months), but if interviewer "inadvertently" confused me on top of my mental state, it might have been game over for me (and them, since I turned out to be an "outstanding" candidate).
The interviewer made no mistake though, they made an observation; they were confused by the boolean expression. The candidate said they understood the interviewers concerns and was also confused, and didn't have an immediate answer. This is all normal and healthy, and something you'd commonly see in healthy and competent development teams.
The only thing I see that's wrong is that the interviewer thinks something went wrong.
> ...the statement even though logical, is not technically right because if we start from the left cell[0][0] == cell[1][1] would evaluate to True and then True == cell[2][2] would evaluate to False given that the cell contains a char.
Interviewer seemed confident ("is not technically right") which confused the candidate:
> I told the candidate about the same and he agreed but he was confused at the same time
Candidates are already in a high stress situation, you don't want to add to it unless you really know what you are doing (i.e. you are specifically looking for deep language mastery).
Interviewer has correctly realized they've done this and learned from it: kudos to them even if too late for this candidate :)
