It's fashionable lately to “ditch” Dropbox for other sync services. The reasons stated are usually around cost or privacy. This is understandable, but for anyone with a significant number of files and/or services using Dropbox, the time and complexity of switching could easily be costlier than what it would be to just continue using Dropbox.
Dropbox has only rarely caused me grief, and only with resource usage. Sometimes the client takes too many of them. Otherwise, it's been reliable and dependable for many years.
I've used Syncthing and Resilio Sync as alternatives. Both are fine, but other services depending on sync don't often support them, meaning I still need to use Dropbox for some of my “stuff”. This puts me in the unhappy situation of keeping things in 2 places. I did this for a while, and it ended up a confusing mess.
iCloud is handy, but only on my Macs and iOS devices. It's also never been as dependable as Dropbox. I've lost things. And stories like iCloud data loss with macos and ios 13 betas doesn't help my confidence.
I use Dropbox on Linux and I once fumblefingered a command and deleted a bunch of files. These were easily restored using Dropbox. I like the way Dropbox works today.
As much as I love to try new things, I don't feel that my file storage and sync system would benefit from the sort of tinkering that be would required to change it.
I'm bucking the trend and sticking with Dropbox.