You've given every person who joins your server the ability to disable echo (and in some cases logging)
The following three control ability to see normally hidden things
"ulx hiddenecho" "Ability to see hidden echoes" -Superadmins by default (You likely don't want to give users this)
"ulx seeanonymousechoes" "Ability to see who uses a command even with ulx logEcho set to 1" - Admins by default (You likely don't want to give users this)
"ulx spawnecho" "Ability to see spawn echoes and steamids from joined players in console" - Admins by default (THIS is the one you likely meant to give, but, we might not recommend - be warned, SteamIDs will show to players too.
There's no way to separate prop spawns from player steamid spawns, as we wrote these commands for administrators, not all players.