Dropbox is the pioneer of consumer cloud storage services, starting in 2007 when no comparable service existed. It is mentioned here mostly for historical reasons as you probably have used Dropbox in the past, at least with the 2GB free tier. It is also one of the most available storage solutions on your mobile device for saving photos and documents.
Dropbox is very similar to Microsoft OneDrive: you install the Dropbox app on your computer and your mobile device and all files saved to Dropbox will be automatically be available on all devices.
Dropbox does not provide any additional cloud service, it is purely focused on storage.
The main problem with Dropbox is that if you are already using Microsoft OneDrive or Google Drive, the Dropbox service becomes completely redundant.
The other problem is that Dropbox is expensive compared to its competitors: A$19 per month for 2TB for single user or $32 for 2TB for a family up to 6 people. Compare this to A$13 per month for 6TB for up to 6 people for the whole Microsoft 365 family service (including Office and Outlook), then I really don’t see how Dropbox can compete at all in the consumer market market.
