Historically, when compared to DRAM (dynamic ram), SRAM (static ram) is more expensive with a lower density, but it's much faster and more efficient. As a result, SRAM is reserved for devices, such as processor caches and microcontrollers, where maximum efficiency and or performance are critical. For devices requiring large amounts of memory, such as a PC, SRAM is too expensive despite its advantages over DRAM.
Has any of today's major advances in semiconductor manufacturing carried over to SRAM technology to mitigate some of its issues? Apple Silicon, for instance, integrates the system DRAM into the chip, yielding improved performance and efficiency, but why not use SRAM instead? With transistors nearing the sub-3nm scale, is memory density still an issue? What challenges are holding SRAM back?