That's not on targe...it's like saying removing stimulus improves immersion. Take that to the limit and it's like he's saying we would be more immersed with text based games! When the target is immersion then more stimulus is required in order to compensate for the fact that it's not real thus our own senses are hampered. Two senses are all we really have in a video game...sight and hearing...and even that input is heavily simulated.
In computer games we depend on the visual stimulus to replace the normal sensations...in fact the more stimulus the more immersed we become. Now, if you cover up one of the stimuli with another one then it defeats the purpose of the first one...so if you clutter the screen with inventory data then yeah it may be distraction, but it also adds more stimulus as long as the screen shows enough of the visuals. Heck...I'd go for an electric shock if my character gets electrocuted...some realizm goes a long way.
I just remembered that we had this same discussion when idsoftware added the damage face in Wolfenstein 3D. Some people thought it was obstructing their view and other thought it was cool ie. the technical details. But, what we learned later was that the visual indication of damage really helped the immersion level. But, id added a switch to turn it off...I think it's the people with small screens that have the problem...with lots of indicators and such their viewport shrinks from 17" down to like 15" and that's just too small for anything these days.