I cannot emphasize this enough: if you actually care about performance, forget about 16GB vs 8GB and switch from using the internal SD card and to an external SSD. I wrote up my experience at https://honeypot.net/2023/03/20/upgrade-your-raspberry.html

Once you've done that, and your max latency has dropped to 0.7% of what it use to be (yes, really, the SD card had 140x higher latency than the SSD on my system), carve out 32GB for swap and call it done. This will give you vastly better throughput on any likely use case that's not purely dependent on RAM size alone.

If I were using this as a portable desktop system, like I am with my uConsole, I'd rather have 4GB of RAM and fast storage than 16GB and the SD card. One of them is fine, just a little sluggish sometimes. The other is pretty nice, until it grinds to a halt for minutes at a time. If `apt upgrade` is your benchmark, SSD >> RAM by a wide margin.