May I ask? Why you need/want a Thunderbolt Dock with a Mac Studio? I get that with a MacBook Pro M1 in a desktop configuration "could be" a must have but not so sure about the advantages of having another box next to the Studio. Am I missing something here?
I bought the TS3+ (and a Plugable before that) before the Studio Display was a thing, and I have been using it with two monitors connected through DisplayPort. Also, I use the TOSLINK for audio connection to my receiver, Ethernet for network and I use USB ports for microphone, camera, scanner, SuperDrive, external disks and a Lightning cable. I also use the card reader from time to time.
I will continue to use it after I get a Studio Display (or possibly two) because the Studio Display only has three USB-C ports, of which none are Thunderbolt. Ethernet and TOSLINK are essential, so if I used USB dongles connected to the Studio Display there would only be one port left.
Besides, I like to have all this stuff tucked away under the desk and out of sight, not hanging off the back of the monitor.
EDIT: I just noticed your question was in regards to the Mac Studio specifically. I have not ordered one, and will be using the Studio Display with a 14" MacBook Pro, which of course doesn't have all the ports the Mac Studio has. Had I intended to use it with a Mac Studio instead I would not have purchased a Thunderbolt dock if I didn't already have one.