I see too many cached folders

Piktures shows the folders that Android lists as containing photos or videos. Some apps store images in such folders, for example album covers, stickers, or cached pictures, and these folders then appear as albums.

Hide these folders

Exclude them:

1. Open More → Settings → FOLDERS → Manage excluded folders. The same screen is in the Albums tab, on the phone: ⋮ → Set excluded folders.
2. Tap Select a folder, or + if you have already excluded some.
3. Check the folders to exclude, and tap Save.

An excluded folder is hidden, with all its sub-folders, from the Albums tab and from All. Its files aren't changed. To bring it back, tap it in the list of excluded folders.

To hide a single album instead, see Hide and unhide albums.

About .nomedia

Android normally leaves out of its list the folders that contain a .nomedia file, so their images don't appear in Piktures or in other galleries. Piktures itself doesn't read or create .nomedia files.