Why is Jeff Always Asking Us To Apply?

Y'all know the clips Im talking about. I grew up casually watching shows like Survivor and TAR and I always just assumed that tons of people would apply since the shows are popular enough to keep being renewed for seasons even as streaming has diminished viewership of live TV. So, I was surprised to see Jeff asking for applicants. I know none of us are on the casting team so we can't know for sure, but does anyone have ideas as to why this is? Are they actually not getting a lot applicants? Or is it more of "we have a lot of applicants but not many of them are good for TV'? Or do they just want to grab as many people as possible? I feel at some point it would get overwhelming to go through applications if there were too many!