They were going to release an Armored Thanos. He has been in the concept art for the movie and other toy leaks for roughly half a year.
I am glad they are releasing him. I dedicate most of my collection space to marvel figures. The armored version and tank-top version are different enough where I will enjoy getting both. The figures represent a character from arguably the two biggest comic book movies of all time.
I mean how many people have multiple iron-men? To the hardcore fan we can tell them apart, but get only a casual marvel fan, and they wouldnt know what armor is from what movie, or might ask why you have the same figure (then you have to explain that the Mark 45 and 46 are from different movies and not the same figure.)
I am using my concept art mark46 as my infinity war Iron man, and I doubt all but a small percentage of the population would even be aware of that. As least armored thanos and tanktop thanos is a start enough difference to take notice.