Request for advice: talk me out of upgrading my PC

Hi, I’ve got a fairly modest computer by today’s standard and I’m looking to upgrade the GPU and perhaps also the CPU. Mostly I use it for playing games and your other typical PC tasks, not much video editing and stuff of that sort. Mostly MMOs, sandbox games, RPGs, CRPGs and the occasional sim or 4X.

At the time I’m having a blast with Baldur’s Gate 3 (me and everyone else), and it runs fine (albeit with a fairly hot GPU topping out around 89 C, but ambient is around 35 tbf) on High settings. Only thing I noticed is some occasionally long turn times of enemies “thinking” during combat. Also been meaning to play Elden Ring but my PS5’s GPU died early in the game (just after console warranty expired), so I’m tempted to get it for PC.

Currently got:

• Asus Prime B450M-A
• Ryzen 5 2600X
• MSI RX 580 8GB
• Corsair DDR4 16 GB (2x8GB dual-channel) 3200 memory
• 650 W PSU

I think the biggest performance gain would come from upgrading the GPU. Where I had something like a 6700 XT (currently at 330 € here) in mind.

Is it nonsensical to also upgrade the CPU to a 5800X3D (currently 320 €) instead of just waiting a couple more years and going with whatever platform is current then? Not interested in buying all new memory nor a higher-rated PSU now. Thinking the mentioned CPU can squeeze at least five more years or so out of this motherboard before I need a bigger upgrade. Perhaps it would also help with turn times?

Probably around 150 € can be recouped by selling my old parts once I have flashed the BIOS and no longer need the old CPU.