If in the last 60 years, had we just put 5 satellites up there, who cares? However, we keep sending more and more satellites up to space into orbit for as long as we can possibly keep them up there. Satellites are expensive, so we want them in orbit for as long as we can. At this rate, if we kept putting satellites up into orbit for the next 10 bazillion years, the sky would darken. Less sunlight would end up reaching the planet's surface. How much sunlight would reach Earth? What's important is: the whole process is fraught with danger.
As Robert Fulghum stated in his book, All I Really Need to Know I Learned in Kindergarten, “.. kids in kindergarten learn to clean up after themselves….”. We don’t always know the ramifications of the things we do. But we do know that if we make a mess and then multiply that mess by 7 thousand, or 7 million, or 7 billion, then things get worse, sometimes past our understanding to know what will happen because of large system complexities.
As our population keeps doubling, we have a much larger human impact on the land, air, and water around us. Our Earth is finite. Yes, it matters how bad things will get, and it matters whether we need to be in emergency mode or not. But the system of making a mess, and not cleaning it up is dangerous, especially when that mess is multiplied by the 7 billion and growing people on this Earth.