OK, that was a real stretch as given that Safe Mode testing you did does indicate there's some kind of software issue. In your listing of apps, determining just which one might be the source of the problem is going to be something of a project.
You could try going into your Settings >> Apps menu and disable half of the apps in your list, restart your phone and see if your connectivity is OK again. If the first half doesn't make any difference, it's probably not any of those apps. Disable the other half of the listing and see if what happens. Hopefully the problem app is in one half of that list or the other. Then it's just a matter of whittling down the list to find the culprit.