We need to generate the backup asynchronously in the background which is why there isn’t a download button. Do you have a folder structure like /Apps/Trakt/2023 in OneDrive?
I’ll have a few updates out tomorrow that will give improved error messaging on the https://trakt.tv/settings/backups page and will also put the backup queue at a higher priority. That should allow the backups to process more quickly and closer to your scheduled time.
Backups are higher in the processing queue now, please let me know if they show up closer to your scheduled time.
The additional error messages are there now too, here is what it will look like.
I found some bugs behind the scenes where sometimes the connected Google/Microsoft/etc account had missing info that we need to actually write the backup. Disconnecting and reconnecting should clear it and hopefully get the needed info.
If the backups page is indicating you need additional permissions, you can disconnect the service at https://trakt.tv/settings first then re-connect from the backups page.
I confirm there’s a positive change in place.
Yesterday’s backup came in approximately 2 and a half hours later than the scheduled time. Today’s was only 12 seconds late 
Thanks for the update Justin!
Just as a heads-up, the backup via email hasn’t worked for me. Not that I need it since Google Drive is working, but I activated it out of curiosity.
Just as a quick follow-up, this is the first week when my weekly backup email came in as well! It seems everything is working properly (and even sending the backups at the selected hour).