The new USB 4 standard will have three main benefits over prior versions of USB.

40 Gbps Maximum Speed: By using two-lane cables, some devices will be able to operate at up to 40 Gbps, the same speed as Thunderbolt 3.
Compatible with Thunderbolt 3 devices: Some, but not necessarily all USB 4 implementations will also work with Thunderbolt 3 devices.
Better Resource Allocation for Video: If you’re using a USB 4 port to transport both video and data at the same time, the port will allocate bandwidth accordingly. So, if the video only needs 20 percent of the bandwidth to drive your 1080p monitor that’s also a hub, the other 80 percent will be free for transferring files from your external SSD.