I have read certain (mainstream media) articles in the last months where the limited supply has been pointed at as being a negative factor due there "just" being 21 million coins (a tiny bit less in reality) to ever be mined. They completely ignore the fact that Bitcoin by default is an extremely divisible digital asset, where they also ignore the fact that back when the price was just under $1000, a lot people couldn't even afford a whole coin anymore. 21 million Bitcoins is just a GUI nomination. We also have GUI nominations such as mBTC and Bits to work with in the coming years, where these smaller nominations make sure the number of units will increase significantly.
I wish people could just learn to use decimal places. Is it really that hard?
I think that the scaling debate and rising fees affect the "unit bias" discussion. As it is, using the "bits" denomination seems pointless, since it can take thousands of "bits" just to cover transaction fees on median-sized transactions. What's the point? And don't even get me started on the merits -- or lack thereof -- of BIP176....
Smaller units will make sense when Lightning Network use is mainstream and people don't need the entire network to validate their transactions. Until then, I think this sort of sentiment will remain common. In other words, I think this is a transition period where people will continue to focus on the BTC unit, and many newcomers still won't understand that you can buy a fraction of a coin.