Allow me to quote the relevant posts, your screenshot is too small to read:
So there is another thread asking about bc and decimal places. It is stated that the client(s) only show 2 decimal places, but there are 8 in total. Now, working on stuff, I find that it would be nice if I could transfer at least 4 decimals precision, but the full 8 would be great.
Looking at the code it seems simple enough to remove the rounding from bitcoind, but what about the receiving side? If it's a non UI client, then it will show everything, but would I be making things overly confusing for GUI clients?
Is there any shortcoming in me patching my client to handle full precision?
I would not encourage using the extra decimal places. They're only intended for future use.
You are correct that above 0.01 can still have additional precision, but the recipient won't be able to see it. The UI will show it rounded down.
I wasn't into Bitcoin back than, but my guess would be further decimals at that point were simply irrelevant, because anything smaller than 0.01 Bitcoin was basically dust. It's funny how it's now worth $200.
When I installed Bitcoin Core for the first time (in 2015), all 8 decimals were visible already.