You can tweak the power limit settings for your application. In many cases you can drop the power consumption (and heat generated) while still maintaining > 90% performance but this will depend on your actual use case [0].
In my experience for many models you can reduce the power limit even further than what has been tested in this guide while barely impacting performance.
I use 2x3090 to train large language models, and mine don't thermal-throttle with air cooling even though they're right next to each other. Eth mining does generate too much heat though.