alt Hacker NewsNo, assembly doesn't always inherently deal with abstractions. It depends on the system involved. I don't really count "microcode" as an abstraction, it's essentially part of the hardware and doesn't even exist on many embedded CPUs. The assembly instructions for all intents and purposes operate directly on the hardware. If you wanted to get really absurd with it, you could say that all of it is an abstraction of electrons.
Embedded CPU assembly is what I do most often, for the last 40 years, and there aren't really any abstractions at all - not even microcode. You have a few KB or ROM and maybe a few KB of RAM, ALU, registers, peripherals, and that's it - no APIs, no kernel, no system calls, no stdlib. Just the instructions you burn into the ROM.
Depending on the ISA, assembly is quite abstracted away from the actual underlying hardware, at least from the viewpoint of a computer architect. It depends on the ISA, of course.
Many common hardware features like out of order instruction issuing, register renaming, and even largely caching and segmentation, are largely or entirely hidden at the assembly level.