Quoted from TigerLaw:First of all, it cleans out all the dummy accounts people made back in the distant past just to manipulate rankings (you'd be surprised how many accounts were created one day, ranked 15 or so games immediately, then were lightly used for a month and then vanished).
Also, back in 2009 (if that's when you were rating and then left the site forever) you never got to see modern games. No WOZ, no Tron, no Dialed In! or whatever. You just saw the games up till 2009. If you stayed on Pinside since 2009 and then just didn't rate anything so be it, but if you vanished in 2009 from the site your rankings should not stay as it is not reflective of the current population in 2017 that has a superior ability to rate games of today to games before 2010 (to a person who has vanished).
Eliminating ratings from non-active users sounds like a possibly misguided reaction to a real problem. It's easy enough to weed out those one day account ratings without affecting all old ratings of former users. After eliminating those, I'd be fine with a formula which reduces weighting of apparently stale ratings (based on date posted, account status/activity). I'd also add that re-editing older ratings should increase weighting, as it would reflect a more contemporary opinion. All this would effectively age out ancient ratings from closed accounts, and keep ratings fresh. It sounds like Robin has some of that already in place.
Thinking about it further, I don't believe my opinion nor my ratings change much over the years no matter what the new games look like. You yourself point out that a 5 year old pre-LCD game is your favorite (I actually agree with that specific opinion) regardless of what has come after it. A couple of my favorite games are 80's solid state, alphanumeric games without modes... years haven't diminished their ratings relative to anything released in the 30+ years since.