I know Enchantment#getName is deprecated and is not recommended to be used anymore, however, this function continued to return the correct name (although badly named) until version 1.21.

for (Enchantment enchantment : Registry.ENCHANTMENT) {
    System.out.println("Enchantment [" + enchantment.getKey().getKey() + "]. getName() return " + enchantment.getName());
}

I ran the code above in two different Spigot versions, 1.20.6 and 1.21. and the outputs are attached below. You can see that Enchantment#getName() returns an incorrect name in version 1.21.

For example, getName() of the Efficiency enchantment returns DEPTH_STRIDER instead of DIG_SPEED.