I think we have to give up on anything being _universally_ accepted.

Even climate change isn't universally accepted, but it's an unfortunate fact and arguing about the semantics of it for another couple of decades isn't going to help anyone.

If 9/10 scientists agree, then I'm likely to side with them.

And in the case of overpopulation, 9/10 scientists agree.

https://earther.gizmodo.com/is-the-world-really-overpopulate...

Did you actually read the article that you linked to, because 9/10 of them do not say that the Earth is overpopulated. There's a lot of talk about sustainability and climate change (which are real concerns), but none of them say the earth is overpopulated, and instead focus on the overproduction of CO2 by a relatively small percentage of the population.