You can purchase any small amount you want, but he’s talking TX fees.
That $1 turns into UTXO dust very quickly on chain.
Discussion
Like I said though I would just have to wait longer. I have a wallet with 40k sats as an experiment. To move that right now i woukd have probably nothing. But in the future im sure ill be able to move them.. actually i think its way less than that
Economically unspendable outputs are indeed something to consider. But high fees are what motivate more efficient use of block space. There are clever ways bitcoin could be used today, but the software to take advantage of the rules of bitcoin hasn’t been written yet.