That discussion is from 2018, that was 4 years ago. Surely things have improved somewhat since then.
> So the question is: Is the reduction of participants from the higher technical requirements significant enough that it weakens Bitcoin? (I honestly don't know.)
No, that's far too simple of a question. A better is: where do you find the balance between technical requirements for the network and the usability of the network for end user?
It makes perfect sense that as the usage grows, the network will become more expensive to operate. More users is more data, and more bandwidth. If you just refuse to increase the requirements an inch, you're refusing to support the growing userbase.
Many other projects have to make such decisions. Your space sim gets more popular -- that costs more bandwidth, requires more polygons on the screen. Do you bump up the system requirements, or do you stall your growth to allow 10 year old hardware to be usable? And pretty much all of them bump the requirements. You can't play modern games on a 386.