The moderately technical solution is a single-file webserver on the computer that supports file uploads, like https://github.com/sigoden/dufs.

Once it is running all you need to type on the phone is the IP:port.

Localsend, if you're on the same wifi network. Works decently for sending files between Android/iOS/Desktop (sometimes on iOS the app must be closed and reopened a couple of times before non iOS devices can detect it, for some reason).

I use magic wormhole everywhere else, servers, vms, etc.

LANDrop

https://landrop.app/

There are some forks since the software was originally opensource but then closed it.

Start web server on desktop, show QR on desktop, scan with phone, phone posts key to route in QR code

QR codes?

Not all desktops have cameras.

The vast majority of desktops do not have a camera.

You can still generate the QR code in the desktop and scan it with your phone camera. The device receiving the file does not have to be the device that scans the code.