You can summon lightning in spawn protection, through the use of a trident and a lightning rod

Start a server and join it

Give yourself operator permissions

Set the world spawn to your current location

Set the weather to thunder

Place a lightning rod within spawn protection

Obtain a trident enchanted with channeling

Give operator permissions to a different player

Remove your operator permissions

Throw the trident at the ground within spawn protection
-No lightning is summoned

Throw the trident at the lightning rod within spawn protection
-Lightning is summoned