I've been using the Juno Jupiter Pro for a while now. It's a pretty awesome dedicated Ubuntu laptop. The main limitation is that it is 3.5 pounds but it does require a large brick so really it's more like 4 pounds. It does have 16GB of RAM and 512GB SSD and an nVidia RTX 3050ti. The second issue is that it does not USB C charge which would be great. The battery life is just OK at 2 hours or so for regular computing and the Ubuntu build definitely works well.
Lucas is using a bigger 13" ASUS ROG X13 2022 notebook and it seems to deal with Ubuntu and the right drivers pretty well, so this is an opportunity to get a machine that is USB-C charged and which has the same capabilities. So on to look for a Windows notebook with USB C. It is just $1300 at Best Buy right now so a great deal. It is getting great reviews as an ultra notebook at 3 pounds (and the charger is USB C so it can be shared with an Apple MacBook).
If you want something from a mainline vendor then a refurbished Dell X15 is not a bad choice. These are $2400 but also are supposed to be USB-C charged and can have a 3070 graphics card. These are typically one generation older so the 11th generation and not the 12th and weigh in a 4.5 pounds, but it is just $1700 for a 15" which is not a bad deal for the XPS 15 9510 with 16GB, RTX 3050Ti and a 4K panel even which is not bad for a name brand system and a bigger machine.