As of April 2nd 2020, I'm testing a new plugin feature created by another Proboard user that allows you to have your own personal image storage space that directly links to Proboards. All users who set foot into the forum now will recieve a message at the top of the forum asking you to link your Cloudinary profile if you have one. (You can also dismiss it permanently) The main reason for this addition is to allow members of the forum to be able to use their own computer(s) as personal storage for pictures and what not, and giving them a space to upload for storage reasons, which then link directly to this forum whenever you wish.
Bear in mind that Cloudinary is a service though that comes with several plans. While I don't think much of anyone will need to go beyond the free plan, the free plan does have its limits to how much you can store on your Cloudinary account. So in my advice, I'd say to use it primarily for uploading your own sigs that you use on forums and reaction images that you frequently use. And hey, it's better than nothing. Right?