And you can let it if they use Storage Access Framework to ask for that permission without them requiring blanket access to all your private data.
Perhaps you should get informed as well.
In the end this is again app developers refusing to do the work to protect privacy and trying to push through the laziest most privacy voilating solution because it's less work.
The person you are replying to has not denied anything you said, nor have they given any indication that they need to get informed. Your comment is wildly misplaced.
What did I say that was wrong? The comment I was answering to - that I assume you read - says: "This Nextcloud app seems to be [...] It isn't a file manager, it isn't a backup utility, it's a cloud provider with local mirroring."
Right, so you don't know the app. What about getting informed first?
I use Nextcloud to backup files to the cloud. I want it to access my files.