Gayle has been excellent when playing in the Championship for the likes of Newcastle and Crystal Palace.
The 29-year-old has found it tough to get game time in the Premier League this season under Steve Bruce.
"The tag of him being prolific in the Championship but not the Premier League is nonsense," Moore told The Athletic.
"I just see a goal machine. Dwight will score goals at any level if given the chance.
"I told him when he signed on loan for West Brom that, if we got promoted, I would sign him permanently because I know he will score goals in the Premier League."