Got a 6900XT on sale for about $700. At the time, it was easily $200-300 cheaper than a second hand 3090.
It's a really solid GPU, and I don't have to worry about NVIDIA's terrible Linux drivers and bloated+jank Windows drivers. Outside of raytracing performance, no huge problems, but even on NVIDIA, you need temporal upscaling to get good framerates with it enabled.
6650xt is very tempting right now but I'm concerned of the driver complaints and all other "QoL" that many claimed they had it better from Nvidia.
NVIDIA has more driver-side tweaks that you can do with older games (mainly DX9 and DX11 tweaks), but most of the complaints about AMD's drivers can really be boiled down to hardware that needs to be RMA'd. I ended up getting a faulty card from ASUS, and I had to get it RMA'd, eventually I got a working replacement (Don't even bother going through the retailer you bought the card from). Outside of VRR/FreeSync having weird black flicker problems with Microsoft Edge, I haven't really had a problem with their GPU drivers. There's definitely a problem with fanboys on online forums and Twitter/Reddit spouting misinformation with literally no sources cited. To me, that's the same as people saying "PC Gaming is expensive, a $2000 gaming PC gets outperformed by a console" last-gen, when that's blatantly nonsense unless they bought a crappy prebuilt from CyberpowerPC.
Radeon Software is a single driver suite for everything, while on NVIDIA, you need to download GeForce Experience and RTX Broadcast separately from NVIDIA's site (or just Broadcast if you download the drivers straight from NVIDIA). Radeon Software also doesn't require an account login (and internet connection) or telemetry/data-collection enabled to use. There's also the option of using RAM as a instant replay buffer, which is useful for when you don't want stuff constantly writing to your NVME (and thus reducing it's lifespan). On NVIDIA cards, you need to use a hilariously ancient RAMDisk software from ASUS, and then set the temporary files for Shadowplay to that drive in order to get similar functionality. NVIDIA Control Panel also takes forever to do literally anything, despite having the UI from a Windows XP program, it's actually sad when Electron web apps outperform that shitpile.
Buying a 6 year old GPU is apparently more expensive now than it was at new (GTX 960)
Yeah, those are old new stock, makes sense that they would be expensive. If you have the money, I'd recommend a 6650XT or 6700XT, due to the VRAM being higher (than any of the 16 series cards NVIDIA is still selling) and DirectStorage being supported, and those two things are going to be important with current-gen games. Buying a 16 series card is basically like buying into a dead-end ecosystem.
Although, if you ask me, Valve either needs to revive the Steam Machine concept, or AMD has to release a 6700XT equivalent GPU for $150. Otherwise, PC Gaming is going to stagnate due to NVIDIA's greed, and everyone else being complacent in the mess they (and Microsoft) made. I've given up on NVIDIA's GPU pricing (or drivers) or Windows becoming any better, I'm in the acceptance stage.