Why my ticket has 20 kg limit with recent booking instead of 30kg

[Rohanmelb]

I recently booked through Malaysia airlines, my luggage showing 20 kg isn't 30 standard

 

[oz_mark]

Depends on the fare. I think Economy Basic is 20Kg.

 

[SYD]

Depends on the fare. I think Economy Basic is 20Kg.

Or could it be aircraft? Years ago I had a flight from Athens to Santorini and the bag limit was 15 kgs! One of those “wear or carry everything you can moments”