I don't know if it's "hassle-free" but adb over Wi-Fi has worked well in my experiences. I tend to use adb over USB for file transfer. Both use command-line utilities so not suitable for all end-users.
I'll try that, though it's not perfect for me. I'm fine with CLI, but my use case for AirDroid is usually dropping some photos from my phone into someone else's computer, while we're on the same network.
Come to think of it, maybe I could just spin up a HTTP server on the phone with Termux, and serve the DCIM directory. And then wrap it into a homescreen icon via Tasker.
