Yes, some Olympic swimmers do wear tampons when they are on their period. From what I have seen, swimming during a period is normal and does not stop a swimmer from training or competing. Many athletes choose whatever feels most comfortable for them. Some use tampons, some use menstrual cups, and some use other period products.
The main things are comfort, hygiene, and confidence in the water. Every swimmer is different, so each one finds what works best for their body and routine. In simple words, having a period should not be seen as a problem for swimmers.
