Don't tell anyone I'm still living in the computer dark ages, it's a little embarrassing. I was probably one of the last people clinging on to Windows XP until it finally was no longer safe, squeezing every last kilobyte of life out of it. This is a recurring theme with me because I'm just too lazy or cheap or a combination of the two. :-)
I was running on a circa 2009 Dell XPS Studio desktop with an i7-920, 24GBs RAM, and multiple SSDS, until 2 years ago when power supply fried, and I swapped to a spare Dell Precision T3500 (similar vintage, and my primary system today. With vast majority of my stuff in virtual machines, moving to new computer was trivial). Other than video/photo editing, system is more than powerful for all of my other uses. I too loved how optimized I was able to make XP. But I did move to Win7 within a year (or so). I waited a couple of years before going to Win10 (which can still be a free upgrade), and I'm avoiding (beta) Win11 (standard Windows every-other PoS desktop OS for last couple of decades) completely at this point.
So, right tool for the job... just recognizing that real-time video, along with some games, are typically the most demanding workload for consumer PCs. Personally, I avoid running with admin rights, am well aware of IT security risks to avoid, and can keep an OS running for many years without major issues. So, upgrading for the sake of upgrading is something I typically avoid (may car is over 20 yrs old, been in same house for 25 yrs, etc. - get quality, configure and maintain them properly and enjoy for a LONG time)
I had a work provided M6800, started OBS streaming with it actually (the only issues being Corp IT security s/w settings incompatible with livestreaming). As much as I prefer desktops, I'm looking to get a modern equivalent of mobile professional workstation with HX CPU, 4 DIMM slots, multiple M.2 slots, etc (such systems just being released)... which may force me to have Win11 as host (but I'll leave all my VMs at Win10 for now). so don't apologize for not upgrading unnecessarily (as long as still getting security updates). but you have a use case now that demands decent power. How much power? .. depends (sorry) and also depends on how good you are at optimizing a setup. Just want it to work, plan to buy a little extra spare 'power' ;^)
@BobK53 - I was lost for a little while as well. With a significant time investment (and an existing deep compute understanding to start with), my use of OBS Studio has turned out well.