I've used Dropbox for personal cloud storage and backup for over a decade. It has almost always served my purposes so very rarely have I even thought about looking for other options. But over the past year or so I've had several problems that led me to look for a replacement. It's not any one huge problem, but rather an accumulation of small problems. It's the fact that Dropbox doesn't actually download files from the cloud onto your local machine, even when you select "make all files available offline", you have to actually go through and right click every single file and folder and tell them all the download individually, often multiple times over the course of days or weeks. And the fact that their Dropbox Backup product has been in beta for years now, which I guess means they want to advertise that ability but they either don't know how or don't want to invest what's required to make it work reliably. Dropbox Backup is an option within the Dropbox desktop app that allows you to select arbitrary folders and files outside your main Dropbox folder and have Dropbox continuously backup and version control those folders and files as well. Seems like it should be a very simple feature, just telling the app to monitor multiple folders instead of one, but it has never worked reliably. I only told it to keep track of my Desktop folder, which in MacOS is ~/Desktop, but I've had tons problems with it. Dropbox doesn't treat Backup folders like regular Dropbox folders. It handles them through an entirely different process. You can't simply delete and recreate those folders whenever you want to. Trying to delete them yesterday actually took me more than an hour, because I had to search through a variety of pages I had never seen before that were completely disconnected from the regular dropbox.com interface. The biggest problem of all was that Dropbox Backup wasn't playing nicely with MacOS Finder and I couldn't send files from Desktop to Trash. When I attempted to delete files from the Desktop, MacOS would display messages saying that the files would be deleted immediately, rather than sent to trash. This continued for over a year. I spent several weeks talking to Dropbox tech support and to their credit they never abandoned me and stopped responding, but after a month they also made zero progress in fixing the problem.
I checked out competing products like iDrive. iDrive is nice and it's half the price of Dropbox, but it's pretty barebones in comparison. And to be honest I really like Dropbox's continuous version control. If my free time is worth $x/hour, then the amount of money I've saved from being able to recover lost versions of files through Dropbox has greatly outweighed the additional $40/year I've spent on Dropbox vs iDrive. So I'd honestly like to keep using Dropbox if I can fix the problems.
So eventually I completely uninstalled Dropbox, deleted all Dropbox applications and stored files from my laptop, and reinstalled everything from scratch, this time with Dropbox Backup disabled and not syncing ~/Desktop. I went back to an old hack I had used for years prior, where I simply created a regular folder named Desktop inside my Dropbox folder and then replaced MacOS's Desktop folder with a symlink to that Dropbox Desktop folder. That gives me everything I want without any of the half-baked Dropbox Backup mess. And it's really easy to do. You just have to do it quickly because MacOS doesn't like not having its standard folders extant in their standard configuration. Just open Terminal and run the commands below (assuming your Dropbox folder is located at ~/Dropbox, otherwise modify the commands below accordingly).
# Create a new Desktop folder within Dropbox
# Move everything from the old MacOS Desktop to the new Dropbox Desktop
mv ~/Desktop/* ~/Dropbox/Desktop/
# Delete the old MacOS Desktop and replace it with the new Dropbox Desktop
sudo rm -r ~/Desktop ; ln -s ~/Dropbox/Desktop ~/Desktop
That's it! That should sync your MacOS Desktop with Dropbox without having to use the buggy beta Dropbox Backup option. Maybe one day Dropbox will complete/fix their Backup app, but I'm not holding my breath. I don't need to. This solution works just fine.