It seems to be that the /trigger command sets scoreboard scores, and if for /scoreboard you need to be op, then shouldn't you need to be OP for /trigger? Sorry if I somehow didn't understand something about these commands.
MC-78625
/trigger command for non-ops
Resolved
Works As Intended
0
The whole point of the /trigger comand is to allow a non OP player to set certain scores to trigger other systems through books/chat. Also there is no security risk as in order for a player to be able to run the command, the scoreboard must be of the type trigger and the player must also first be enabled.