do universities see playing soccer a meaningful extracurricular activity?
Especially if you also play club sports, they understand the level of commitment.
Being a captain may help a little.
Do what you like and enjoy. Do a few things for 2-4 years. Showing commitment is important not the league /level your in. The longer your in it then maybe you can mentor the younger students in the sport. If they have an end of year banquet maybe you can help plan it. If there’s a summer camp for younger kids maybe you can be a helper or counselor.
Yes, it is a meaningful activity. How much so depends on the college. You can look at a college’s “common data set” to find out (Google it with a college’s name to find it, look for the section that describes how the college weighs different factors).
Colleges have all kinds of activities outside the classroom. They will want to know who can handle their academic load along with those other activities. Playing a sport in high school and the time commitment necessary helps demonstrate that, whether you continue to play your sport in college or not.
Yes. Especially if you are good at it.