That is not true. It is better to get the hot air out of your case as quickly as possible. It does not matter how much air you get in. If your air inside the case is hot, it does not make a difference. As it goes for dust, you're going to take it anyway, either with positive or negative pressure.

Positive pressure is better for sloths. They never clean anything.

The whole point is to get hot air out because you don't want your parts to become hot. Also according to airflow 101 on toms hardware page, positive pressure creates "Stagnant air" which heats up your internal pc parts in the longrun which is dangerous. Also, it just makes sense to take hot air out. You don't want hot air in your pc, you want cool air. And as far as dust, you are right. Negative pressure will create more dust but there are many ways to prevent this. And cable management falls DIRECTLY ON THE PERSON!!! Have your desktop 6ft from the ground since dust accumulates from the ground up. Also I'm not saying that people that use positive air are lazy asses but you should expect to at least conduct maintenance on your own pc about every month. I would prefer every 3 weeks because it isn't too long and it not even HARD AT ALL TO CLEAN DUST. Again, isn't the big picture about performance? I believe so, if people are afraid of a little bit of dust and they would risk performance over FUCKING dust then I don't know what to say because it isn't COMMON SENSE!!! These bright men over many others are actually not afraid to make a video and be judged showing the ACTUAL truth of airflow to settle this annoying ass dispute over which is better. And alast, the TRUTH is in front of the white of your eyes. You can deny it or you can accept it. I don't care if you use positive or neutral pressure people are entitled to their own likings, I'm just glad that these men just finally proved which one was better.