If you increase max.poll.interval.ms that says “it’s ok to spend time processing a large batch of records” and you’ll gain throughput if you can process larger batches more efficiently than smaller ones.
To decrease max.poll.records says ”take fewer records so there’s enough time to process them” and would favor latency over throughput.
Also consider that both are configured fine, but something else is causing performance issues within your poll loop. I would explore that first before changing configuration so you don’t mask a bigger problem.