@melissawm not sure if they count as big-tech, but I use Backblaze B2 for my own client-encrypted backups using arq https://www.backblaze.com/b2/cloud-storage.html . YMMV on how reasonable their privacy policy is, but at least it’s clear enough to make your own decision. I think it’s good enough to host encrypted backups.
Are there any (free or paid) services for data storage/backup on the cloud that are not big-tech, have a reasonable data privacy and protection policy? I'd like to back up documents and photos currently spread across Dropbox and Google (with a local physical copy) for redundancy