TTGN is a news site for all aspects of tabletop wargaming and covers news of virtually every system/model manufacturer under the sun. It certainly isn't anti- any company or manufacturer. Quite the opposite really.
GW and
PP news pops up all the time, as Zac tends to derive much of his news from manufacturers' press releases, and of course
PP and
GW both produce their fair share of those! He doesn't indulge in rumour mongering though, which for many extreme fans is the only kind of news that counts

.
Not surprising therefore that those who inhabit
GW-only and
PP-only ghettoes are ignorant of its existance.
The purpose of the poll is really to give the owners/readers of the site some info of what games folks who use the site are playing and/or buying for. It doesn't claim to be representative of all gamers everywhere. However, being a very popular site, it does still have credibility.
Nothing stopping anyone who is bothered from registering and voting if they want to, whatever their preferences. those that only play one system are as welcome as anyone else. Who knows, they may learn something of interest to their hobby...