Are you sure? I just checked my wallet and Electrum shows all address you have on Addresses Tab along with some receiving and change address in advance after last address which involved in a transaction.
Besides, i don't see any option to show only specific amount of address on Addresses Tab
I don`t know how much address will be show, but certainly just a few. Each derivation path is able to generate millions/billions of addresses.
I just thought that it is safer to use that console function, because he might have generated an address in some weird way and it might not be displaying.
Electrum won't know about addresses it hasn't derived yet so both approaches do the same job. They search the list of addresses that have already been derived. The GUI one is just easier for most users.