Is It Necessary?
No.
That's important.
If you've been eating pineapple your entire life without soaking it in salt water, you haven't been doing anything wrong.
Fresh pineapple can be eaten immediately after being properly cleaned and cut.
Millions of people enjoy it that way.
The salt-water technique is simply an optional preparation method.
Some people swear by it.
Others don't notice much difference.
And if you enjoy the natural flavor and texture of fresh pineapple, there's no reason you need to start soaking it.