An infinitely increasing population is a recipe for disaster. There are very real limits to water tables, arable land, and so forth. Exponential systems always crash.
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.