I have been looking into this issue myself since I have an 8 year old workstation with an Nvidia GTX 1080, which by the way performs great with Enscape.
The main issue I have found is the power supply requirement for the new Nvidia RTX series. I have a 280 Watt power supply in my trusty old Dell T5400 and I would need a dual-slot rated at 320 W to run the new 30x monster cards. Upgrading is not an option. Is best to buy a newer more powerful system with no bottlenecks.
That said, the RTX 2080ti is a hell of a card by many metrics and far less expensive than the newer generation. I would get that one for my T5400 even if I could only get 80% out of it due to the limitations of my current chipset.
280W system supply with a 1080? Yikes. AND it's a low end OEM PSU? Surprised it's lasted this long to be honest. I have a Corsair 750W PSU for my 980 lol. And the same one on my other 1080ti machine. The perks of building your own PC.