I think that's correct. (And until this year Powell was an assistant coach at Oregon, so perhaps something rubbed off.) I believe that the NCAA record is 7.
From the NCAA site:
Seven career triple-doubles:
Suzie McConnell, Penn St. 1985-88 7
Louella Tomlinson, St. Mary’s (CA) 2008-11 7
Danielle Carson, Youngstown St. 1982-86 6
Six career triple-doubles:
Nicole Powell, Stanford 2001-04 6
Alyssa Thomas, Maryland 2011-14 6
Samantha Logic, Iowa 2012-15 6
Five career triple-doubles:
Joskeen Garner, Northwestern St. 1993-96 5
Shalee Lehning, Kansas St. 2006-09 5
Brittney Griner, Baylor 2010-13 5
Most triple-doubles in one season:
Danielle Carson, Youngstown St. Sr. 1986 6
Nicole Powell, Stanford So. 2002 5
Tasha Pointer, Rutgers Sr. 2001 4
Chelsea Hopkins, San Diego St. Sr. 2013 4
Alyssa Thomas, Maryland Sr. 2014 4
Sabrina Ionescu, Oregon Fr. 2017 4