You will obviously get somewhat biased answers here, and I haven't even tried it personally.
But one thing I can say for certain (because it's a common complaint I've heard) is that rclone is infinitely more configurable to your needs. Google drive stream is really not meant to be user configurable beyond the basics.
I mean here are it's settings. It's pretty sad... rclone has almost more settings for the Google Drive API specifically than drive stream has for the entire software system.
https://support.google.com/a/answer/7644837?hl=en
Rclone can talk to pretty much anything. Drive stream is for drive - period. And only if you have a Gsuite to boot.
Rclone is an ecosystem. Caching, encryption, remote control, webUI. Can can choose the modules you need and configure them in detail. Drivestream is whatever the setup is and the handful of settings you are allowed to tweak.
Encryption... I mean... It's worth mentioning twice. Call me paranoid, but I'd never upload my data to the cloud unencrypted. It's very unlikely google actively spies on people in the sense that they scrounge through your data, but they certainly do run hash-scans.
I'd be interested to hear if anyone thought Drivestream was actually better on some front - except for it being very easy to install