A while back I got fed up with the same thing and started using this little Mac tool called CloudMounter. It basically turns all those cloud accounts into regular drives right in Finder, so pCloud, Backblaze B2, Mega, whatever, they just show up like external disks. No more launching separate clients or dealing with their sync quirks; I drag files between them super easily, and it doesn't eat up my local space since nothing has to fully download unless I'm working on it. I've had multiple accounts from the same service mounted at once too, which helped when I was sorting old backups. Check it out here if you're on Mac: https://apps.apple.com/us/app/cloudmounter-cloud-manager/id1130254674. Not saying it's perfect—sometimes connections act up after macOS updates—but for me it's cut down the chaos a lot without feeling like extra bloatware.