I tried all the steps you suggested, but those steps did not fix it.
Then I tried the clean boot for, by disabling everything in startup and disabling all services in system configuration. Upon restarting, my wifi features actually worked. I could connect to wifi, like I was supposed to.
But then when I followed the steps listed to isolate the service that may be causing the problem, by systematically starting the services and restarting each time, to find out which one results in disabling my wifi connection, my wifi connection hasn't returned, even after disabling every service again. I have tried repeatedly to recreate the conditions that resulted in my wifi connection working that first time that I tried the clean boot, but I have been unable to do so. Now, even with all services disabled, it still can't connect to wifi. I don't know why it worked that one time, but hasn't worked since, even though I've tried disabling all services again, just like I did that first time.