The S3 also supports "Touch 1200" speed toggle to enter the bootloader .
Adafruit TinyUF2 bootloader
with mpflash you can flash using :
mpflash flash --board ESP32_GENERIC_S3 --bootloader touch1200
https://github.com/Josverl/mpflash
Originally posted by @Josverl in micropython/micropython#17525 (comment)