Population isn't really exponential excepted in limited conditions, such as the remarkable medical advances of the past 100 years. When the average lifespan was 45 and the possible lifespan was, say 100, then an exponential jump was possible. With the possible lifespan pretty well reached, population isn't growing quite so fast.
Nor is there any real shortage of arable land. I live next to one of the largest cities in the world and arable land is being gobbled up for development simply because it is nearly worthless as arable land. By the population gloom and doomers' own numbers, we could support at least ten times the planetary population we have.
There are various organizations, as well as studies done by our own government which say fishing stocks have markedly declined because of population growth. More people means more pollution - live in any large city to witness this. And I don't want to live on a planet that is wall to wall people.