You mentioned getting 40 series Nvidia GPU later. But which one? Bear in mind when the 50 series gets announced, there will be a a huge uptick in 40 series prices because dealers will continue hoarding them. It happened when I got my 30 series card.
More importantly, let's assume you will get one. Which one are you targeting? 4060? 4060Ti? 4070?
If you're looking for the cheapest way out, get a used i5-11400f. 32 GB Ram and 4060 or above. You'll be set for at least the next 2 years.
If you're not looking at eeking out every single frame from your game, the Intel 10400f and 11400f are absolute beasts for the price and gaming performance per watt.
The only downside is that you'll be locked to a PCIe 3.0 bandwidth since the boards supporting 10 and 11 series don't have 4.0 support afaik. Consequently, your SSDs will max out to 3000MB/s speeds.
You get better options with what your 1st post mentioned with i5 12400 and whatever board you want to get with it. You'll get the CPU and MOBO combo for less than 20k brand new. And unless you're playing at 4k Ultra settings, I doubt these CPUs will bottleneck any card below Nvidia xx80 or equivalent.
On the other hand, if you want a stable upgrade path and an eventual high end card added to your system, absolutely go with the 7600 or 7600X and combination board/RAM.