I am a hypocrite, but there is really not that much need to upgrade CPUs anymore. Even a ten year old chip seems completely adequate for day to day use. I played with a N100 recently and those things are incredibly capable.
(Ignore my AM5 workstation with 192GB RAM in the corner)
I really wish I would've bought 192G when it was less than a few thousand dollars!
Depends wildly on what you're doing.
I'm a gamer, often playing games that need a BEEFY CPU, like MS Flight Simulator. My upgrade from an i9-9900K to a Ryzen 9800X3D was noticeable.
You say that, but DDR6 will double the memory bandwidth over DDR5. This means modern systems will go beyond 200GB/s memory bandwidth just for the CPU alone.
I rocked my Haswell i5 until last year when I built a brand new machine around the 9800x3d. Along the way I upgraded it from 8gb of ram to 32gb, got a gen 1 pcie3 NVME, and went through successive hand-me-down GPUs starting from a GeForce 770 to the RTX 2070 it has now.
In fact my wife is still rocking that machine - although her gaming needs are much less equipment intense than mine. After a small refurb I gave it (new case, new air cooler, new PSU) - I expect it to last another 5 years for her.