The folly of anecdotal evidence

Studies show that people are more likely to look at articles with pictures, even if said pictures have nothing to do with the subject at hand

During my old Arcana High campaign, one of my players took on the role of a gnome illusionist named Syrasi Tumblebarrow.  Coming from a long line of celebrated arcanists, she was expected to follow in her family's footsteps when she received her admission letter to Highstone Academy.  However, Syrasi was was intrigued by another school of magic, one forbidden in gnomish culture: necromancy.  At first I didn't really have much of a world set up, especially for gnomes, but over time things evolved organically.  Syrasi was played very well, who acted as the party's moral center and injected interesting story ideas which I rolled with for later sessions.  At first gnomes were but tinkers who lived in burrows and liked whimsical magic, but by the campaign's end they were so much more than that.  They were conservatives torn between isolation and interaction with the wider dangerous world, yet at the same time innovators in technology.  A culture where the widespread ability to speak with animals resulted in a progressive, almost vegetarian respect for beasts of burden.  A society where the concept of death is not just the physical kind, but also used for the mark of outcasts who are no longer welcome among their people.

In conclusion, gnomes are not an unpopular race, and are in fact just as common a playable option as elves and humans.  How can anyone argue otherwise without denying the experiences of my own gaming table?  All those gamers complaining about the race feeling superfluous, or being outright removed in various settings, are either dishonest or projecting one isolated incident as some sort of common trend!

The story of Syrasi is true, but the conclusion of this last paragraph is not.  In regards to certain arguments among the D&D fandom I often see anecdotal experience of one's own group games trotted out as some sort of trump card.  The idea that something can only be a trend, a problem, when one personally experiences it.  The idea that the comments of others are less legitimate by virtue of being told by someone outside one's circle.  I see this pop up a lot in regards to martial/caster disparity in Pathfinder, although by no means is it limited to that.

I once did a solo Labyrinth Lord game where the PC was a Paladin.  In one session she was supremely unlucky and out of 4 hours of gaming she only rolled a single D20 result higher than 10.  Our holy warrior was not doing so well and would appear to be underpowered due to the luck of the dice, but in another session she was decked out in heavy armor and fighting berserkers who laid nary a scratch on her.  I could use either session's experiences to argue that the Labyrinth Lord paladin is underpowered or overpowered solely by what I experienced, but that would be missing the bigger picture.

Gaming sessions, even when the same adventure is played, can often go off course or result in a very different experience.  DMs incorporate house rules, make alterations to personalize the adventure to their world, and configure a lot of behind-the-scenes stuff the players may never see.  A party without a magic-user and thief plays and feels very differently than one which contains both.  The dice may not go our way and turn our usually-skilled hero into a bumbling unfortunate soul.

Anecdotal experiences have their place in discussions; it is a useful tool for playtesting, after all.  But it is one story among many other games, one path in a world full of crossroads.