My new ESP32 is bricked?

TL;DR: press 'boot' button when flashing ESP32. At least some of them.

I have connected newly bought ESP32 to usb cable and try to flash it with micropython image.

(micro) maho@dlaptop:~$ esptool.py --port=/dev/ttyUSB0 erase_flash
esptool.py v2.6
Serial port /dev/ttyUSB0
Connecting........_____....._____....._____....._____....._____....._____....._____

A fatal error occurred: Failed to connect to Espressif device: Invalid head of packet (0x5B)
(micro) maho@dlaptop:~$

Does it mean that my ESP32 is broken? I thought so, but it appeared that it flashed properly when I pressed "boot" microbutton while erasing flash and flashing.