I've been very happy with ProClip mounts in the past - https://www.proclipusa.com/vehicle/dashboard-mounts/9734-chevrolet-silverado-1500-series/2019
Full disclosure, I do not have one in my current truck, but the following look like they'd meet your criteria of not blocking the vents (the first one might come close to blocking part of the windshield, but the second two definitely wouldn't):
https://www.proclipusa.com/product/213561-center-dash-mount-extra-strength
https://www.proclipusa.com/product/835471-proclip-console-mount or https://www.proclipusa.com/product/835470-proclip-console-mount
Just a note, in addition to buying the mount, you also need to buy the device holder.