“I think we should …” is not an opinion, it is a factual statement about an opinion ("we should…) which you have, and thus it’s either true or false depending on whether you have that opinion (“it’s true that you think …”) or not (“it’s not true that you think”).

An opinion might be right or wrong if it’s an opinion you should or should not have, some of course are neither because not everything in life is just yes or no. Opinions about facts that are false or facts that are true are easily categorized as wrong and right opinions.

“75+25=110” is an example of a true statement and thus a right opinion to have. “We should change 75+25 to be 100” is a false statement and thus an opinion that you shouldn’t have. “Pirandello is better than D’Annunzio” is neither true nor false, but you can still think that and hold it as an opinion, like I do, “I think Pirandello …” is a true statement about my opinion.

In my opinion you are entitled to hold an opinion regardless whether it’s true or wrong or neither.

Abaci and mechanical differentiators did the job just fine for a couple centuries.

Well, opinions can be wrong. When someone says an opinion is wrong they don’t mean that it’s not true that you have that opinion, but rather that it’s an opinion you should not have.

And some opinions like any other ideas are just wrong. You are entitled to have them, just as much as you are entitled to be wrong, it doesn’t change the fact that it’s wrong.

For example “we should change math so that 25+75=100” is an example of a wrong opinion.