I have owned an Arduino MKR WiFi 1010 for a number of years and recently I have been looking a dev board with similar or better specs for a project. I found the Arduino Nano ESP32 which costs half the price of the 1010. What I'm trying to figure out is why is the ESP32 so much cheaper than the 1010 as it seams to be significantly better. The ESP32 has 5x faster processor (and its dual core), 64x the flash memory, 16x the SRAM, and a 384 kB rom. They both have WiFi and Bluetooth, and similar pins. The ESP32 has USB-C and is smaller and lighter. The only downside I can find is it does have battery input plugs of 5v out.
ATSAMD21G18: this is the primary MCU, on which your sketch program runs.
ESP32: this is on the u-blox NINA-W102 module used for Wi-Fi and BLE communication.
The MKR WiFi 1010 also has an ATECC508A crypto element chip for applications such as secure network communication and a high end BQ24195 power management chip that provides support for powering from and charging a lithium battery.
These extra parts add significantly to the bill of materials cost, the complexity of the PCB, and the overhead for writing, maintaining, and supporting the firmware for each of those parts.