Truenas uses KVM for virtual machines. So that will allow GPU passthrough, but may require command line and config files to do it. For docker this seems relevant: https://forums.truenas.com/t/electric-eel-nvidia-gpu-passthrough-support/11797
When you read files from the ZFS filesystem it will automatically keep the files in RAM. This is called the ARC and it is why people frequently recommend having a lot of RAM with ZFS. The ARC is very effective, automatic, and has no risk because it only caches reads. A cache drive is a secondary ARC generally using a fast SSD. The problem is that it generally only helps performance when you are reading lots of small files multiple times. This is because ZFS does so well reading large files from HDD that it doesn’t make much of a difference.
In short: If you already have the drive and want to play with the feature, go for it. But if your going to spend money on the drive, you will probably be better served spending it on more RAM.
I assume the cache drive is for your ZFS pool. You probably don’t need that.
What about GiB?
You have missed my point. People are already putting in effort at their jobs. When they do get time to relax they don’t want to be required to do a second job.
If this was a car community you would be telling me that everyone needs to know how to do their own oil changes. If this was a baking community you would say everyone needs to make their own bread. A gardening community would say growing vegetables.
These can be valuable and rewarding skills, but just because it is important to you doesn’t mean it should be required of everyone.
You know most people play games as a fun leisure activity. Telling them that they need to do a ton of work just to participate is going to be a hard sell except to a relatively small group of people. That is a large factor in why so many people buy consoles.
I want to make sure I am understanding what you are intending to communicate correctly. At first I thought you were basically saying, “normies need to get good”. But in reflection you could be attempting to say, “Linux advocates are communicating unrealistic expectations which lead normal people to frustration and disappointment.” Or is your intent something else?
Part of me is bothered by those explanations, but if I had to explain GitHub to a tech illiterate grandparent with that much screen space I don’t know if I would do much better.
Be aware if you have the iGPU as the only video output device and passthrough to a VM it will no longer show what the host system is doing. This would be referred to as a headless server. I would suggest making sure you can SSH into the host before doing that. LearnLinuxTV has guides for how to do that with best security practices.
Docker works differently, so it may not be an issue with that.