That indeed could work, and it looks like Belkin's Thunderbolt 3 Express Dock HD[1] actually does this. Though in this case, Thunderbolt is limited to just 2 (1 for downstream and 1 for upstream).
I guess the biggest benefit of USB 4 hub is that allows the hub to have more than 2 Thunderbolt ports (the upcoming OWC Thunderbolt hub has 1 upstream and 3 downstream) and no longer have to worry about unplugging a device breaking a chain (usability problem).
I guess the biggest benefit of USB 4 hub is that allows the hub to have more than 2 Thunderbolt ports (the upcoming OWC Thunderbolt hub has 1 upstream and 3 downstream) and no longer have to worry about unplugging a device breaking a chain (usability problem).
[1]: https://www.belkin.com/us/p/P-F4U095/