#Format for every entry is "<namespace>:<path>,<amount>". Tags are supported, must be in the format of "#<namespace>:<path>". Namespace may be omitted to use "minecraft" by default. May use asterisk as wildcard parameter via pattern matching, e.g. "minecraft:*_shulker_box" to match all shulker boxes no matter of color.
attack_speed_overrides = ["minecraft:iron_sword,8.0", "minecraft:diamond_sword,-1"]
java.lang.IllegalStateException: Data -1.0 at index 0 from source entry minecraft:diamond_sword,-1 does not conform to filter
This makes it impossible to make any kind of item slower than 4 (which is very quick already)
This filter seems pointless as Minecraft has no issues supporting negative attributes
Screenshot example produced with give command