Simply that the distance identifier in certain commands breaks the command and just doesn't run it at all.
Setting the following command in a repeating command block it will not kill the fishing bobber
execute as @p run kill @e[type=minecraft:fishing_bobber,distance=..2]
Setting the following command will kill the fishing bobber the tick it spawns.
execute as @p run kill @e[type=minecraft:fishing_bobber]
Please do not mark unreleased versions as affected.
You don't have access to them yet.