My daily driver right now is a mid-tier Tiger Lake board. You can get the equivalent for sub-$300 on Amazon. The client doesn't need to do much in the modern developer flow, running a browser, an X server and an ssh client is 90% of anything that needs to happen, with the occasional Linux Wayland client from the VM thrown in (Thunderbird for personal mail, occasional use of Audacity, stuff like that).
I have a couple of Samsungs and a Pixelbook. You can BYOD with Chromebooks, too, so you can pick smaller, lighter ones or ones with bigger screens than the standard offerings if you’re willing to pay for it.