Regarding the first Gen threadripper, it will be decent for productivity tasks but it will struggle for gaming. For gaming you absolutely want Zen 2 silicon as the instructions per clock is much higher. For 4k 60Hz maybe things are not as CPU dependent, but I still would not drop back to Zen silicon. You can see here how Zen is comparing to Zen2 in games.
The 3600 will be just fine, in fact perfect for gaming and streaming, and be okay for video editing. If you really need to save money
https://www.amazon.ca/AMD-8-Thread-Unlocked-Desktop-Processor/dp/B0876Y2TMZ/ (edit: 3300X is preferred here but absolutely not worth $270CDN when you can get a 3600 for $20CDN more) will game well but probably hurt your streaming and editing. You would also have this option
https://www.amazon.ca/AMD-Processor-Wraith-Stealth-YD1600BBAFBOX/dp/B07XTQZJ28/. Even though it has the 1000 nomenclature it is actually a Zen+ silicon so it meets between having cores and IPC vs the Zen silicon of the TR (this is not true for every 1600 CPU, only the ones with "AFBOX" in the SKU vs "AEBOX").
It seems everything has a $100CDN premium on it though which is sad.