No Wi-Fi on Xperia XA2 (pioneer)

I installed the latest /e/ on a Sony Xperia XA2. The WiFi MAC address is shown as “02:00:00:00:00:00” and the wifi toggle button is stuck in the disabled position. I cannot see or connect to Wi-Fi networks. The other peripherals (GPS, cellular network, etc.) otherwise work correctly. Any ideas?

This phone was previously running LineageOS 17.1. I know you have a disclaimer saying downgrading from OSes based on recent Android may cause “instability”, but this is not very helpful - LOS 17.1 is very buggy, even by Android standards, with broken GPS and broken 4G. I have little choice but downgrade, or stick to 3G networks only and no GPS…

(Side question: why is downgrading such an issue? Why can’t one just rewrite the entire flash on a phone with the OS image, deleting all previous information?)

In addition to this, battery usage is very high and screen brightness control doesn’t work.

I am amazed at the fact that Google, Qualcomm etc. managed to produce something with a similar level of quality as Windows ME, but made it even worse by removing the equivalent of wiping your entire HDD and reinstalling from scratch…