Turns out the reference models might have a issue with it's coolers contact to the die. https://www.tomshardware.com/news/amd-investigating-rx-7900-reference-hot-spot-temperatures
I own a 7900xt and during gaming the Temp usually reaches 70-73 and junction temp around 80-85+ haven't seen 90 yet. I have a good airflow case, Cooler Maser NR400 (Full mesh front with 2x140mm fans, and full mesh top). Hopefully it can be fixed with some washers or something.
To be honest your temps sound fine. Mine Ramps up to 110c junction and 70 gpu edge in minutes in basically every game and starts throttling board power. If you haven’t seen 90 yet it honestly sounds like your card is working fine.