A key question is: did the Egyptian women wear the modest uniforms because they “chose”, or because they wanted to avoid being killed when they returned to Egypt?
A previous poster pointed out that the uniforms are chosen by each team. I suspect that if any team member had refused to wear the uniform, she wouldn’t have been permitted to participate.
This whole tedious discussion springs from the fact that some people ignore the topic (reasonable modesty in sports dress) and reconfigure some detail into an offense and an occasion for huffing, just because it involves Muslim volleyball players who dress like Muslim volleyball players.