@perrry
I use the sim on pc
It is a nice rig which bought last year december
x299 msi pro 10gb
Intell core i9 xgen 10900x cpu 20HT cores 30% usage
Corsair Liquid cooling icue 180
64gb corsair 2666 MHz ram
3090 msi suprim 24 Vram running 100% at +/- 73°c
Psu Corsair HX1000 watts
Also use a 4k beamer optoma z45
Ofcourse the sim will use more ram if lod is set higher or resolution is set higher, but not that much unless you scale up to 8k or higher with using upscale of secondary scale ( in usercfg.opt higher than 2.000000).
The terrain lod is more on Vram, while object lod is more on Ram so higher setting result automatic on higher usage.
I have noticed that if fullscreen is set above monitor 4k res, and secondaryscale in usercfg.opt is set below 1.000000 it works very nice in upscale renderscale, but if other way around like 2550 1440
In fullscreen and secondary scale above 1.000000 and renderscale 200 its is more demanding and will give some stutters while loading textures.
Personally i use higher terrain lod and use less objects lod ( for terrain around 6 up to 9+ and object i use max 5, depend on where flying) i fly mainly GA Cessna 172sp classic this because im not really a fan of the glasscockpit, but more of steamgauges.
Also noticed the difference in colours if change overall resolution setting, i fine tune colours in freestyle nvcp.