Similar to ObjC reference counting? (Not sure, I don't use ObjC and am not an expert in it, it just reminds me of what I've heard of it, so honest question).
The only thing it does is to automate the retain/release calls of Cocoa classes, or classes that offer similar API.
It doesn't apply to any other C like types from Objective-C, and basically the generated machine code is hardly different than when devs keep doing those calls by hand.
Yes there is some potential for the compiler to remove needless set of retain/release pairs for short lived objects, it doesn't happen all the time though.
Swift, also despite the ARC marketing, made the sensible choice to go with ARC, because one of the key designs was interoperability with Objective-C runtime.
As shown by RCW/CCW runtime used by .NET for interoperability with COM's AddRef/Release, there is a lot of more machinery required to have a tracing GC cooperate with RC scheme, so it was understandable this route wasn't chosen for Swift.
As some papers prove, current performance isn't that great, which is also Swift 5.5 is bringing a more aggressive optimization, which is turned off by default.
Check WWDC 2021, "ARC in Swift: Basics and beyond".