It really depends on what you are doing with your system...
On my main PC I want the full Linux Desktop experience, including some Gnome tools that require webkit - and since I am running Gentoo, installing/updating webkit takes a lot of RAM - I would recommend 32 GiB at least.
My laptop on the other hand is an MNT Reform, powered by a Banana Pi CM4 with merely 4 GiB of memory. There I am putting in some effort to keep the system lightweight, and that seems to work well for me up to now. As long as I can avoid installing webkit or compiling the Rust compiler from source, I am perfectly happy with 4 GiB. So happy actually, that I currently don't feel the need to upgrade the Reform to the newly released RK3588 processor module, despite it being a lot faster and it having 32 GiB of memory.
Oh, and last, but not least, my work PC... I'm doing Unreal game development at work, and there the 64 GiB main memory and 8 GiB VRAM I have are the absolute bare minimum. If it were an option, I would prefer to have 128 GiB of RAM, and 16 GiB of VRAM, to prevent swapping and to prevent spilling of VRAM into main memory...