Honestly, if you are in the US I would say you should consider a 10% tip the lowest you should go since servers make their salary off of tips almost exclusively. If someone provides you a service, you should pay for it, even if it is not exceptional. And yes, leaving the steak on your plate was too passive. Even if the server noticed your steak on the plate, the onus is still on you to tell them what is wrong and how you would like to rectify the situation.

I will say it is very commendable for you to seek other people’s perspectives on this situation. It takes a good person to ask for advice and potentially criticism. I hope you will always lean towards being kind to others, especially those in the service industry and retail.