New features and minimum number of users

Sometimes the owner of the product declares wanting a new feature in our information system, but he wants it because our users want it. But the real situation is that 1 or maybe 2 users have expressed their wish to the owner and now he extends it to all users.

Because each additional feature or modification adds complexity, this should not be done at the request of one or two users if there are more than 10000 users.

My question is: is there a good guideline as to the number of users who should be positively affected by the change, so that it is profitable? In this case, for example, I can say "we have to evaluate your demand and if about 20% of our users are interested, we have to do it".

I'm not talking about bug fixes or financial profitability.