You've not proven zero point why Snorlax is better as an anchor. Snorlax's attack stat may be high, but his stamina is so low that it's doing less damage, but here, let me enlighten you how STAB Pound/Hyper Beam Blissey's stamina state is superior as an anchor:

"A Pokemon's Energy (Stamina) can also be replenished during battle by using Fast Moves or by taking damage."

http://www.pokemongodb.net/2016/05/energy-stamina.html

Blissey's stamina allows it to take more damage, therefore charge HB faster than Snorlax, meanwhile while outlasting Snorlax as a pure anchor even with damage. 250+HP vs 400+HP for damage charging is far superior with Blissey. It's just a fact.

Most of your comment is an attack about nothing. If I'm going to use 6 attackers, or reenter battle with a second team of 6 attackers, I will do that as necessary during raids that require full attack teams or extra support. You failed to mention and read that many raid parties are different. When you can find a full one with generally good people, you can use an Anchor. You may never need to use your anchor, but in those matches that I decide or the party decides it's a good idea to do it that time, we've always won. With people using Snorlax's as Anchor's, they usually die too quickly and don't get off the damage that Blissey does.