Adafruit Huzzah espcomm_open failed
I had to install the SiLabs CP2104 drivers and reboot.
Make sure you don't have 2 connection (Arduino IDEs, VS Code with PlatformIO, ...) open. Also, I kept pressing the reset button the first time.

https://learn.adafruit.com/adafruit-feather-huzzah-esp8266/using-arduino-ide