Top 20 NuGet ratelimit Packages

Super simple API throttling / rate limit framework based on attributes
Rate limit your actions and funcs by throttling and debouncing them.
Plugin for ServiceStack that adds rate limiting to ensure endpoints are protected from misuse
Functions for tracking event frequency and applying rate limits.
AspNetCoreThrottler is an ASPNET .Core request throttler that delays requests to maintain a desired request rate, or if a hard threshold is met, it will completely reject requests.