I'll believe that the 6.5 Creedmoor is mainstream when I see the rifles and ammo at Wal-Mart alongside the 243s and 270s.
So you're in doubt of the 6.5 Creedmoor's viability if it doesn't have the popularity of the 243 or 270 ala Walmart. Pretty high bar, one not even the 300 WSM (the most successful cartridge roll-out of the last 50 years) can equal.
You're irrational.