The biggest performance boost from an upgrade in the last two decades was switching from a Western Digital VelociRaptor HDD to a Samsung 840EVO SATA SSD. That was going from 6ms to 0.06 ms random access latency.

The performance boost from switching from Windows to Linux wasn’t perceivable even on Gentoo where I literally compiled for the exact hardware, I had and used a custom debloated monolithic kernel. But it got me a massive boost in user agency and freedom of choice.
You can’t beat two orders of magnitude reaction latency reduction with an OS change. Windows is bloated. But it’s not that bloated (at least Windows XP, 7, and 10 weren’t; didn’t try 11).
I play on Gentoo btw.

I am a gamer and can confirm. For gaming, iGPU is objectively low-end. Doesn’t mean, you can’t play games on it. Current iGPUs are probably better than what games were made to run on two decades ago.
I did have fun playing a selected set of games on an iGPU a decade ago. Dedicated GPUs just give you more pixels, more textures, more shader quality, more geometry, more FPS, and nowadays more AI inference capabilities. Some game genres profit a lot, some don’t at all.

If the SOC makers want their hardware to be popular for longer, they really need to add mainline kernel support.
I looked at them as a tinkering platform. But I don’t want to buy something which is probably abandoned in a few months.

This is learned behavior though. It’s not obvious. I learned it from my parents. He obviously didn’t.