I'd say there are lots of factors in play. We didn't think junior tennis was a waste of time and money on our son. But we also limited spending to a couple grand each year and realized his odds at a college tennis scholarship were much lower than his odds at an academic scholarship to college. He's now attending a top state school on a full tuition scholarship, because our greater focus in high school was on academics.
We spent a lot of time attending tennis events in the greater Atlanta area during his high school years. Lots of parents and tennis players fantasized about tennis scholarships. But with equal time, effort, and money, I think the academic scholarships are easier for most of those students to get. GA has a Hope/Zell Miller academic scholarship program that pays for many more scholarships than tennis ever will. If your're not a top 20 B16 in GA, you're probably better off to switch your focus to academics.
Our son still plays tennis in college, though recreationally rather than for his collegiate team. He's simply not that good. He approached the top 100 in B18s in the state, and his UTR is 6. Could he possibly have been a UTR 7 had he doubled his practice time in his high school years and had we spend twice the amount on coaching? Sure. Buthe still would not have been a strong tennis scholarship candidate at any school he really wanted to attend.
I went fishing with a guy this week whose daughter started at a D3 school on a tennis scholarship. It didn't end well, so she returned to GA and attended a school she liked a lot better on the Hope/Zell Miller academic scholarship.