iPhone 8 totally freezes when trying to connect to WiFi

I have an iPhone 8 Plus that completely freezes when trying to connect to the internet. In an emergency situation (I can't even power off the phone to reboot it, it totally freezes up). I was having this problem on an older iPhone as well and thought it was a hardware issue but now I am convinced that it's a software problem. How can I analyze and fix this?

I'm running iOS 13.1 (17A844).

Solution 1:

Try to solve it with:

1. resetting network settings
2. trying wifi networks with different settings
3. reinstalling iOS

Resetting network settings:

Settings > General > Reset > Reset Network Settings

Trying wifi networks with different settings:

1. try to disable bluetooth, airdrop, and cellular data first (try to activate wifi while in airplane mode)
2. try wifi networks with different settings like frequency, encryption, name, device vendor, internet connected/disconnected
3. start with unecrypted wifi, disconnected from the internet

Reinstalling iOS:

1. make a full backup to iCloud
2. make a full local iTunes/Finder backup (don't rely on single backup type) (Tip: use an encryption - more data are backed up)
3. reset the phone to DFU mode
4. restore iOS with iTunes/Finder
5. setup as a new iPhone
6. connect to Wifi; did it help?
7. if the phone is now stable, proceed to reset the user data from settings and restore your backup
8. connect to Wifi; still stable?