With the announcement of further artifact reforging that is on the way with Omen in the December version update, it's natural to be curious whether or not the item level will be increased.
As mentioned during the Reddit AMA, the development team is not planning to increase the item level cap past 119. They feel that even at item level 119, the equipment currently available, as well as equipment coming in the future, has a wide variety of options and power, which can be used as stepping stones for increasingly difficult content levels.