I agree! In the last 2 weeks, this has completely failed. I also found that NOTHING fixes this. I completely agree that these steps do not work anymore. I don't know what update occurred, but I'm sick of it and have given up. I hate this forced security!
Only got my samsung phone the other day so only just got round to trying the smart lock feature, it worked fanasically for the first few times I used it inside my home then for no reason it stopped working, I've tried deleting location and resetting it but have to use pass code or fingerprint every time I want to unlock it, seems like this issue has been going on for quite a while, a shame, it was great for the 10 minutes it worked!
I found a solution on another site. It worked for two different Samsungs.
Go into Google Maps and select Google Location History. When you get into your google account , make sure only one device is enabled (namely the phone you are using). Smart Lock now works