The short answer
Yes — fresh pineapple is a fine treat in small amounts.
Why
Pineapple is sweet, tangy and full of flavour budgies enjoy. It's acidic and sugary, so keep portions small, and use fresh fruit — canned pineapple is packed in sugary syrup and should be avoided.
How to feed it
Offer a small piece of fresh flesh with the skin and hard core removed.
How much & how often
A small piece occasionally.