For your kid with social anxiety I absolutely recommend setting up opportunities for him to be away from home without parents by himself or with his brother or a friend.
Both my kids have anxiety. My oldest has GAD and social anxiety. This kind of scaffolding is crucial IMO for kids with anxiety. I would get on it right away. Plan some weekends where he and his brother or friend go do something w/o you. Don’t wait until summer. And if the college he ends up attending offers a pre-orientation option definitely sign him up.
As for less “real life” due to COVID, sure, definitely, but it was more things like the summer camp D22 was going to go to in 2020 got pushed back to 2021 and then they all had single rooms instead of sharing and had to wear masks, etc. Also Driver’s Ed got messed up so she started driving a year or two later than she would have which has made me really nervous about her driving to and from college this year.