SRAM is used in every CPU, not just microcontrollers. Registers and cache are usually implemented as SRAM. The false distinction this article makes between registers and RAM is misleading and indicative of the author's general ignorance of computer architecture.
It's not misleading in the least unless you're a pedantic smartass who wants something to complain about. TFA uses terminology which "Reader Daniel Hooper" will understand, and in which RAM is a synonym for "main memory". Which is the colloquial meaning of RAM outside of hardware design labs and pedantic smartassery.
