You make some very valid points. I started on Quora. I've been writing there almost a year and have 29mil views and 10K+ followers in that year.
Quora started what will be their end in my opinion. Think of Myspace and now Facebook. Will facebook ever meet the demise of Myspace? Probably, but much later down the road.
Quora has been doing it wrong from the get go. they are trying to copy Medium in almost a pathetic poly to save the sinking ship. Sorry Quora, there are more holes than one sinking your ship, and the water is rushing in at an alarming rate.
Maybe think "outside" the box and not copy another business almost "word for word" that will never end well, I don't care how many readers you have.