I don't think all surveys are worthless, I think some surveys are much better at pointing out the flaws in people's perception of reality than in reality itself.
If one were to survey people on gluten-free diets, they might find that gluten-free diets are common and effective at preventing a whole slew of medical disorders. If one were to dig deeper and try to actually diagnose some medical disorder and determine if a gluten-free diet provided any benefit, those claims would quickly fall apart.
The same thing happens with guns. You ask a group of people with a pre-conceived notion that guns make them safer if their gun has made them safer and the results (with the 3M number) might imply that guns prevent >2 crimes for every 1 violent crime that's reported.
who really tells a stranger on the phone that they have guns
Who tells a stranger on the phone that they don't have gun. Why not just leave the door unlocked and tell them your alarm passcode? By your logic, wouldn't it be just as likely that surveys overestimate the number of guns?
Citation needed:
most violent crimes aren't reported
most defensive gun uses no violent crime is committed because the gun prevents it by causing the criminal to run away before attacking the victim
many of those had pre existing violent histories
there are 4,500 unknown on there, many of which are likely gang related or drug related
Why would anyone assume that the unknowns contain any higher percentage of gang-related violence than homicides with a reported cause? Why would anyone assume that violent crimes where guns are used defensively are rarely reported, but violent crimes where the aggressor uses the guns are accurately reported? Why would a person use a gun defensively and then not report the crime? Sure I just prevented a robbery, but why would I want to get the cops involved? That robber probably learned his lesson. Plus NCIS is about to come on...
The sad thing about your blatantly biased arguments is that they're unnecessary. An unbiased look at guns shows that gun ownership, for the vast, vast, vast majority of people, is pretty boring. It's very unlikely a gun will be involved in a crime in any way. But so many gun owners are so wrapped up in this lie that owning a gun makes you safer, that they reject all the evidence pointing to opposite, and even invent scenarios in which their gun has made them safer. It's a totally unnecessary argument. People should be allowed to own guns BECAUSE gun ownership is fairly safe.