The bold above is important. But there are other factors involved as well. Academics vs. Athletics. Willingness to travel. Etc. Several players on the 23u team I coach play for the same local D2 college. The college team carried 22 players on their roster for 2018, but 31 players showed up at tryouts in the fall. One girl I know personally that was cut chose this college because it is close to home and is well renowned for nursing (her career choice). She certainly could have pursued nursing at another institution and may have improved her chances of playing softball, but chose this college strictly for academic and financial reasons (she is commuting). She realized up front that her odds of playing were diminished due to her decisions. But I do agree that all else being equal, most athletes will be able to find a place to play if they are willing to expand their search enough.
This is true. I could put together a reasonably competitive D1 team with players who are attending the University of Florida who are not on the team and are not playing anymore but are there for other reasons. Some are there because they chose to go there over playing, some due to cost, some transferred there when they didn't like their first choice of college (or hated playing softball there), some are grads of a JUCO and decided 2 years college softball was enough, some just came 'home' and I am sure there are many other reasons.
I also suspect @risbeall could also name a very good team of current UF students no longer playing - and that it would probably be a completely different group of girls.