We had a tyre blow out on a motorway in Scotland and I had to try to describe to the breakdown company where we were. I knew the name of the motorway by looking at Google maps but the area around us was utterly featureless and there were no nearby landmarks I could use to describe our location more accurately.
I had the W3W app so tried to tell them the location using that but unfortunately the wind and traffic noise made it nearly impossible for them to understand the words clearly enough and then I realised they didn't have the app at their end anyway.
The best way to sort out the problems with W3W is for a better system to replace it. That system needs to be open and widely adopted - it's crazy I can't send my location easily to someone without asking what apps that have on their phone.