Nothing official was outright stated in yesterday's State of Play regarding armor, but Insomniac did slip in a glimpse at its screen in Ratchet & Clank: Rift Apart, showing us that the gear isn't just cosmetic. In fact, it seems like a completely revamped version of the old system.
In the original games, there were incremental sets of armor that would unlock as the one prior was bought, with each giving better defense, but the price would get steeper and steeper. One of these sets has come back a pre-order bonus, the Carbonox armor. Based on all the bonus, pre-order, and deluxe edition rewards, it was unclear if armor was going to be cosmetic only, but evidently, that's not the case.
As seen in the screenshot below, there are three different pieces of armor, the helmet, chest, and boots. Each seems to have varying stats, with a bonus for having the full collection. What this likely means is that the armor you get for pre-ordering or getting special editions will be its own collection with its own bonuses. Whether this will make the early game easier isn't known.
The armor's name pictured is even a reference to the Lombax Praetorian Guard, the elite warriors of Ratchet's people. Alister Azimuth, who you meet in A Crack in Time, was one of these soldiers, and we've even held a Praetorian wrench and worn Praetorian boots before.
There's a lot more than just defense being offered from armor, at any rate. As seen in the image above, armor brings with it improvements such as better melee damage, more Raritanium earned, more XP, more Bolts, etc. Based on this screen, it's also confirmed that we'll be seeing pirates again, but will it be the beloved ones from Quest for Booty and Tools of Destruction? Perhaps. All the same, Rift Apart is shaping up to be one of the best Ratchet & Clank games to date.