Why a 20-cent gift is impossible on Bitcoin (and free on Nano)
Try to send $0.20 of Bitcoin to a friend who has never used it. Two things stop you.
1. The dust limit
Bitcoin nodes refuse outputs below about 546 satoshis. At current prices that is roughly 40–50 cents. A 20-cent gift is simply not relayed.
2. The fee
Even above the dust limit, a simple transaction is about 140 virtual bytes. At a few sat/vB the fee is tens of cents; during congestion it can reach tens of dollars. The fee is paid to miners and does not depend on the amount sent, so it is a larger share of small transfers.
Nano
Nano has no fee market and no dust limit. Each account has its own chain, transfers are confirmed by representative voting, and a new account can receive any amount. That is why nano.gift can give thousands of tiny gifts: the network cost of each one is zero.
Compare live numbers: Nano vs BTC.