How long before steak is at room temperature? I've got a piece (of about 300 grams) dry-aged rib-eye in the fridge, at around 6 degrees Celsius. I want to let it "get to room temperature" (which technically is about 21 degrees Celsius for me) before I cook it up to about 55 degrees Celsius core temperature.

Is there any good rule of thumb to determine how much time I should minimally / optimally let it sit outside the fridge before slapping it into the pan?
According to Serious Eats, a 210 gram steak in sitting in a 21° C room managed to go from 3° C to 10° C... in 2 hours. For a larger steak going up all the way to 21 degrees, it would take longer. The take-away from that article is that it's not worth it and does not affect the resulting steak.