With the digital release this past Tuesday of The Avengers: Infinity War comes new details in a Director's Commentary bonus feature as it is learned both Thanos and the Infinity Gauntlet are permantely damaged.
If it wasn't clear in the movie, you can check out the above image still, which does show the Infinity Gauntlet damaged after the "Snappening," which saw Thanos use the Infinity Stones to kill half the universe.
Director Joe Russo offers: "See there, with his Gauntlet and the arm, the power that it takes to use all six Stones is significant, and clearly damaged the Gauntlet and damaged Thanos permanently."
In the comics, the Infinity Gauntlet, Infinity Gems and its user are all-powerful, but we see in the MCU things are a bit different. The Avengers: Infinity War saw Peter Dinklage's Eitri the Dwarf create the Gauntlet to house the Stones for Thanos, and it was also revealed in Guardians of the Galaxy that ordinary people can't use one of the Infinity Stones, let alone all six of them.
Regarding Thanos and the Infinity Gauntlet being "permanently" damaged, it remains to be seen how that will play out in The Avengers 4, because it seems possible using the six Infinity Stones in unison again could reverse things.
Last we saw of Thanos at the end of Infinity War, he was pretty happy with things, but we know there is still another movie coming out, so the Great Titan might not be content for long.