Totem Golems are needed for the early strength anyways, and I'm not too excited about a 5/5 for 5 mana, even if it is free late game. Granted, I'm not implying you would run the life gain totem or any garbage like that, but passing over the early game power of TG feels like a mistake.
The problem with the deck was you'd just be run over due to lack of ability to have a strong opening. It had all the mid-game power in the world, but if the game is decided early that's all there is to it. Perhaps a 5/5 taunt turn 4 will be enough to stem the bleeding, we'll need to see. Depending on what happens to our friend BGH we may have to start considering Earth Elemental as well, especially now that lava shock is being run more commonly. A turn 4 5/5 taunt followed my a turn 5 7/8 taunt may be monstrous.
You're missing a very important concept that makes this card great.
You don't need any totem cards in your deck to make it beat the vanilla test. If you hero power once the card is about on par with 5/5 stats plus taunt for 5 mana. This is not exciting, but it can be enough to keep you in the game.
If you have Totem cards in your deck the card is straight up broken. After turn 6 in a totem deck this is very likely to cost less than 4 mana. A 5/5 Taunt for <4 mana can result in a HUGE tempo swing.
There are lots of shaman combos and early game plays that give this card some serious power.
The bad hand opener: You are forced to hero power on turn 2 and possibly turn 3. This will usually cause you to lose the game, but being able to lay down a 5/5 taunt on turn 4 gives you a good chance to stabalize.
The big Tempo swing: This card protects & has synergy with weak totems like Flame Tongue and Mana Tide. A 5/5 taunt for <5 mana might allow your Mana tide totem to actually live for 2 rounds.
Any turn the TfB costs <2 is about the same as a Druid using both of their Innervates. On turns where that happens they can run away with the game if you don't have a board clear. This is very similar where it is so much tempo your opponent just won't be able to keep up unless they have a clear.
In Arena the card is very good.
In constructed it has the potential to be the foundation of a good deck.