The project aims to protect you from malicious USB device. If someone will try to connect a USB device with unknown descriptors (your PC has not seen them before), then that port will be blocked and the attacker will have no chance to steal/destroy your data through USB ports. Under the guidance of Tobias Mueller, the final product of the project will bring a more secure environment for users and will put GNOME on a higher position on the security domain.
More and more people are studying methods on how to block or clean a malicious software. But, today, the threat can even come from something more physical.
All the devices pose a risk. Even a small USB device can have a huge impact on your system. Regarding the intention of a person he may use a modified USB device to “play” with your personal computer.
You will never have full security for a computer, but there are methods that can enhance it. There must always be an equilibrium between security and usability. By creating a too secure medium the workflow of the user may be disturbed, thus the user will disable that security method to keep his work pace.
The project Disable USB on lockscreen does not have this throwback. When the computer is locked, it is clear that the user will not be doing any work on his PC involving USB ports.