I bought an Instagram account with 75,000 followers, and decided to run some tests to see if Instagram was worth spending a lot of time on (for Kopywriting Kourse stuff).
You can see all the numbers/graphs/charts on this page: https://copywritingcourse.com/social-media-strategy/
Turns out by not posting to Instagram for a few days, we lost 60X the exposure vs when we were posting. Yikes!