Neither of my kids used all ten spaces. My daughter just graduated from an excellent LAC. I think she had about seven spaces filled in. Don’t fret about this. Especially now, when everything is a mess. In fact, filling in ten spaces in the current situation might raise eyebrows.
I actually think “less is more” might be quite important for the coming cycle. If students can a find a way to show they were able to stay involved in their ECs over the last few months, it will probably be a boost to their application.