Why does the penny transaction have to confirm in 10 mins? Currently, and for at least a couple of years, you will likely still be able to send 0 fee transacti

Why does the penny transaction have to confirm in 10 mins? Currently, and for at least a couple of years, you will likely still be able to send 0 fee transactions. The time for them to appear in a block will increase however. Have you heard of Lightning (https://lightning.network https://lightning.network)?