Ivy Bridge is third gen.
Skylake is sixth gen and seventh gen would by Kabylake. Kabylake does have Vulkan support, but this is more dependent on the Graphics stack than just the generation of the Intel GPU.
Skylake (sixth gen) kind of marks the beginning of more stable Vulkan support.
Your workload determines your need.
Nvidia 3060 will have its own vRAM, whereas the Intel will share system RAM.
Your Nvidia card will have thousands of Cuda cores and ray tracing, whereas the Intel GPU will have limited shader throughput and only have light duty Vulkan support.
I do not know if you need a dedicated GPU or if the Intel integrated GPU is sufficient for your needs.
But I post this advisory in case, knowing what work or play you do, you could use a grounded comparison.
You're right, Skylake is 6th and Kabylake is seventh gen.
My graphic workload is limited, not at all similar to gaming.
The system requirements for the devcad-software are:
- A PC running true Windows 10/11 (32 or 64 bit).
- No assistance for emulators or virtual machines.
- 400 Mhz processor**|
- 4 GB of RAM (or more, depending by Windows version)
- About 50 MB of free disk space
I found for sale a refurbished HP EliteBook 850 G6 that suits my needs I think - would you agree?
- processor: Intel Core i5-8265U (Whiskey Lake)
• Processor speed: 1,6 GHz (4,1 GHz max. turbo)
• RAM: 16 GB DDR4
• disk: 256 GB SSD (NVMe)
• Videocard: Intel UHD Graphics 620
I agree - those specs are well beyond the min specs you said you need. That is good since often, minimum specs are a bit too lenient...
That looks like a good choice.
And that laptop is nonlonger available 
But found another one, with an Intel Core i5-1135G7-processor.
Google AI says:
Intel Core i5-1135G7 does not use Ivy Bridge graphics, and therefore, the limitations associated with Ivy Bridge Vulkan support do not apply to it.
The i5-1135G7 is much newer and fully supports Vulkan, whereas Ivy Bridge (3rd Gen) does not have native or proper Vulkan support.
Is the full support of Vulkan an advantage, or a disadvantage regarding running the DevWing 3.exe under Zorin?
It's definitely a larger advantage as most things linux have (or are in the process of being) transitioned to Vulkan over OpenGL. There will of course be things that still use OpenGL, but that is not something you have to worry about for the most part, as anything you buy will cover those needs and then some.
Excellent, thank you, I'll go & try to make a purchase 
Well, I purchased a nice laptop equipped with RTX3060, and including Windows11 ready to be configured. However, I don´t want W11, but a dual boot system with W10 and Zorin, each on its own partition and sharing a data partition.
The idea being that if I cant get DevWing to run under Zorin, I can use it on Windows, and process results further in other tools under Zorin.
As this dual boot-install is a topic on its own, I've created that topic and will return here with a success story or with new support requests.