This past week's Rust update brought some big changes to the way the first-person survival game works, including the removal of the XP and levelling system.
Developer Facepunch Studios detailed why players won't level up in Rust anymore, noting that it "completely changed the feel of Rust as a sandbox." Facepunch's Maurino Berry explained how the game "was no longer about new encounters and enjoying your time in the game world, but instead about how to level up as quickly as you can." This resulted in the game becoming boring once you had levelled to the max, making for an unsustainable gameplay model.
"New items we haven't even thought of yet would need to be hacked into certain levels, which would cause a never ending balance nightmare and item bloat (it was already ridiculous when you'd reach a level and have 12 things unlocked)," Berry continued.
"Eventually we'd like to never have to wipe and just have decay and resource management take care of the server, [but] XP was not compatible with this goal without all kinds of workarounds and hacks forced in like some sort of prestige system."
Berry concluded with the fact that XP negated the "'making lemonade out of lemons' feel" that Rust excels at, where your loadout would be consisted of whatever you could find and use.
Replacing XP is the component system, which makes everything craftable from the moment you start. This means no more locked items or blueprints. However, items beyond basics require the use of a component to craft, and these can only be discovered in the world components can't be crafted. Additionally, players will see the return of radiation, which has been remixed a bit. You can read more about the latest update on the Rust devblog here.
One note that Berry makes is an issue where the game chugs and pauses periodically. He says that if players experience this, they should press F7 and send an error report to the developer, mentioning "you're experiencing the same issue highlighted in the devblog."