[NextHendrix]

On the whole, at this point in time, I agree. For general purpose NVM stuff you're better off going with the less exotic, but SRAM isn't suitable for this specific use case. Some eNVMs are essentially analogue (CBRAM, OxRAM, PCM etc) whereby you can partially set a single memory cell much like a variable resistor. MRAM obviously had its specific two states so is unsuitable for neuromorphic computation, and SRAM is the same.

I disagree though that 22nm is the limit for (STT) MRAM and ReRAM, they both have excellent scalability.

SRAM scales nicely but is volatile, takes up lots of area and obviously isn't BEOL compatible. You can stack MTJs between metal layers just fine.