Depends.
For gaming (even light gaming) I'd pick the 5600 MT/s option. This is because the iGPU shares memory with the CPU, and iGPUs are very bandwidth hungry.
However for average day-to-day use memory bandwidth is less important as long as it's good enough (and 4800 MT/s is plenty), so for that I'd pick having more memory.
32GB 4800 MT/s costing about the same as 16 GB 5600 MT/s is odd. Quickly looking at prices here in the US the 32 GB is around 60% more expensive.
Tends to vary a lot here in Canada.
Amazon sometimes has reasonable prices but Best Buy and other retailers either don't sell 5600, or it's very expensive
32 is more than most need today but it's going to be needed at some point in the future. If budget is a concern consider bringing your own.
If you don't have an application that needs 32GB of RAM I would take the faster 16GB. You can upgrade later if you need.
Ideally I’d like to purchase the optimal/best value ram now and not have to upgrade it for a long time
For general day to day and "light" gaming you're not going to see much of any difference in transfer speeds, but you will notice a speed improvement from having more memory to cache. I'd choose the 32gb for that reason.
You'd likely see better graphics performance with the 5600mhz kit just due to extra bandwidth, especially on the Ryzen APU option that's more dependent on the memory speed to set the IMC/interconnect speed. But I don't think it's worth cutting your total memory by half- at best you'd likely see a 5-7% fps increase.
32gb 5600 😎
Haha that'll be the goal if i can find it reasonably priced but, in Canada prices seem to be a lil wack sometimes