[NavinF]

> A microcontroller with WiFi connectivity built in

ESP32 modules are $2 on LCSC and come with a built-in wifi antenna

> So designs that are priced at less than $5 is kinda a requirement for me. Because I sincerely believe I'm stepping into new and unexplored territory

No, your requirements are the same ones that every cheap IoT device has. Open up a $5 smart switch and see how they manufactured it for $1

> simple architecture which includes parsimonious memory modules or only two registers total, for example

What are you on about? Using an unusual instruction set will increase NRC, cost per MCU, and power consumption. Low power ISAs are a scam. Race to sleep if you wanna save resources