Engagement rate benchmarks vary based on a lot of factors. The biggest factors are the channel, the follower count, and the niche. At a broad level,
0.73%-2.5% is considered standard,
2.5%-4.4% is considered good,
4.4% and anything above would be exceptional.
You should compare influencer engagement rates against similar creators (similar in terms of follower count, and audience) where possible, instead of using generalized benchmarks.