Ok, You can say 0,00000001 BTC. We don't need another words, we can say deci, centi, mili, micro.... "dong" exemple se applies.

Yes exactly. The words Sats is all you need, the word Bitcoin becomes unnecessary and slowly becomes like the word Bullion for gold, used only by traders and such. Just a silly branding move, that's all. Build the Bitcoin brand, then throw it all away for the Sats brand.