At the moment, the only clue is that the UF2 Loader is causing some issues. I built the latest version of clean (without screen or other libs) MicroPython from the sources with a simple script that connects to WiFi, hits an endpoint, and saves the logs of the whole process on the SD card.
Conclusion:
- uf2 loaded via UF2 Loader 2.3 - the script does not connect to WiFi
- uf2 loaded directly onto the Pico via USB bootsel - success
I’m surprised because other firmware also loads through the uf2 loader and the Wi-Fi works normally with them.