For DIY, ESP32 replaced the Raspberry Pi as the default board. A Pi is a Linux computer. An ESP is a few-dollar MCU with Wi-Fi and Bluetooth already on the chip.
What it actually does
That is enough for sensors, MQTT, HTTP, and a small display. Cheap SPI/I2C panels plus LVGL cover status screens and simple graphics. You do not need HDMI.
A Pi needs an SD card, a clean 5V rail, and an OS you will update. An ESP boots in milliseconds from flash and runs one firmware image.
Why it ate the nodes
Deep sleep is why it ate the Pi for nodes. An ESP sleeps in µA. A Pi draws hundreds of mA just to sit there. A Pi-as-sensor is the wrong computer.
Small enough to be the device
The module is coin-sized. You drop it in a printed case, a wall switch, a remote, a sensor puck — the board is the product. A Pi still wants a plate, ports, and a brick.
The community already did the boring parts. Printable cases, PCB templates, ESPHome/WLED-style firmware, IDF examples you can clone and flash. You start from a case and a repo, not a blank schematic.
Firmware is cheap now
The old tax was firmware skill. AI removed it. Describe the board and the job; Cursor will write C, Arduino, or MicroPython that flashes. Pick any language you can read.
Start from ESP-IDF, not a random Arduino sketch. IDF is FreeRTOS, Wi-Fi, BLE, NVS, OTA, components. Drop the project in Cursor, open hello_world, then add GPIO, a web server, a display.
Keep the Pi for cameras, browsers, and Docker. For a networked thing on the bench, use an ESP.