The size of the audience really isn't a factor..
I have played for over 10,000 people, a few times in Sea Isle City.. Outdoor music festival..
And upwards of 8,000 people several times in Wildwood.
The only folks that we can see are the people in front of us... not much different then the 100 people we play for at a senior event..
BTW: my first concert solo performance was at the age of 12.... on accordion.. I didn't know I was suppose to be nervous
Rarely if ever have I been nervous about anything I have done in life.
I have been zeroed in to do my best at times.. Competitive
in sports and auto racing, bike racing etc.