I once used an Anecdote as evidence and later it turned out I was right. Therefor anecdotical evidence is correct. And Trillium Bar on all Realms is currently seeing a Prize increase among with a "Quantity available" drop, just as I suggested.
https://theunderminejournal.com/item.php?item=72095
Blizzard has introduced some Profession leveling posibilities exclusively with Pandaland mats and is trying to compensate the demand by enabling gathering Professions to also be levelled in Pandaland, so on long term the Ghost Iron and its pruduct, Trillium, prizes may even out later on but at the moment they will remain higher than in 5.2 for a while.