A fast way to sync local files with Proton Drive? (here exploring rclone)

I want to create a sync system between newly available Proton Drive and my local filesystem. However, since it's very new, it's only barely supported by rclone (I'm lucky to be on openSUSE Tumbleweed because rclone in my other distros don't support it), and it doesn't have a sync client for Linux yet. I've considered 3 options: 1. mount the whole drive using rclone mount and work always online, but that's slow and sluggish and requires constant Internet connection; 2. mount drive with rclone mount and sync the folders I need using the tool [unison](https://github.com/bcpierce00/unison) . But my testing shows that it can take a very long time for the software to browse for changes... Even though when the scanning is done it's pretty fast for the correct/copy; 3. use rclone bisync. But it's advertized to be in testing and not very stable, and anyways I have the same problem that I have with unison, it's very slow to browse for changes... So if anyone has a better idea how to do that ("that" being setting up a sync system where when I change/add/remove something either on the computer or the drive, the change propagates to the other side immediately — or at least, fast, like, under a minute delay), please help!

rclone v1.64.2
- os/version: opensuse-tumbleweed (64 bit)
- os/kernel: 6.5.9-1-default (x86_64)
- os/type: linux
- os/arch: amd64
- go/versiorclone v1.64.2
- os/version: opensuse-tumbleweed (64 bit)
- os/kernel: 6.5.9-1-default (x86_64)
- os/type: linux
- os/arch: amd64
- go/version: go1.21.3
- go/linking: dynamic
- go/tags: none
n: go1.21.3
- go/linking: dynamic
- go/tags: none

That's the latest version of rclone. I'm using Proton Drive's cloud storage solution. rclone config redacted gives:

[proton]
type = protondrive
username = my.username
password = XXX
mailbox_password = XXX
client_uid = XXX
client_access_token = XXX
client_refresh_token = XXX
client_salted_key_pass = XXX
replace_existing_draft = true
### Double check the config for sensitive info before posting publicly