At the risk of sounding like a pig...
I have definitely noticed.
I can see why you would connect these two issues but I don't know if I would.
There are plenty of cases where women compete in a sexualized environment where sex appeal is part of the sales pitch. It definitely exists and is a problem.
However, I think beach volleyball uniforms may actually come from an organic place. The sport literally grew up on the beach and people played it in beachwear. Most of the old-school players (including Walsh Jennings) learned the game on the beach. I think it is legitimately part of the habit and culture to wear the type of "uniforms" you mention.
I think a new generation may change that dynamic. The sport has become more integrated into the sports mainstream through parks and intercollegiate athletics. There are now an entire generation of players who have made it to the highest levels without ever playing on an actual beach.
Just so you know. I am a huge volleyball fan and would watch them if they played in parkas. Beach Volleyball in particular holds a special place for me. I lived on South Beach in the early 90's when the game was coming alive and used to play on the Beach there. I was never all that good but it gave me an appreciation for the sport. To this day, it is my answer to the classic sports talk radio argument about which sport has the best athletes.