Why the reddit survey may not be accurate or trustworthy

It has selection and sampling bias; however, there are 4 questions:

  1. For respondents, were the results accurately reported? The answer to this is apparently yes.
  2. Does it reflect the largest publicly available sampling of D2 players opinions? Yes
  3. Do the results correlate with opinions across multiple forums? Yes
  4. Does one need to survey everyone to get a sense of what the larger interrogated population want within some error limit? No