I think this is quite small for an enormous application like Gravit Designer.
Certainly but the whole point of distributing a “portable” version is that the settings go WITH you. If you copy the program onto a flash drive or run from a cloud service that you use to sync your workspaces, you want the settings to come with you. Files saved to those locations are not going to sync between machines (without jumping through a lot of hoops).
Are the 17 megs of files just temporary or non-settings files? If not, I think what you’re looking at here is a “no-install” version that skips the installation process. That is useful for other reasons, but not portability.