this is a predictable worse latency due to CPU throttling, i.e nothing is suddenly introduced in the system. but the other case is worse i.e a non critical microservice can cause outage on your critical microservice.
imagine some non critical system like blog-service suddenly causing 2-3% new order creation failures
Fixed queue, so it'll only take as many as it can process and reject the rest, which can be used to do scaling, if you have a cluster. With shares it would think it has all the CPU cores available and oversize the queue.
