Shaman wiki gives bad advice.

[Byrjun]

I'm curious who wrote this, and if they ever played a shaman before:

For pure Mana consideration, a higher WIS *dramatically* beats out over a higher STA

That said, there are some meta-considerations as well to be taken into account:

When you reach 0 Mana, you are OOM. When you reach 0 HP, you are dead. Therefore, HP are obviously important.
The higher your HP, the bigger your "Cannibalize buffer" is, i.e. how much overhead you have to play with before feeling vulnerable.
Since it's "easy" to reach your stat caps, any +WIS above cap is wasted and should instead be giving you +STA (and vice-versa).
Draining your Mana pool is better than draining your HP, in that you regain Mana faster while medding than HP.
Draining your HP pool is better than draining your Mana, in that others (esp. Druid, Cleric) can refill your HP for you much more easily than your Mana.
None of this takes any special HP or Mana regeneration items into account.

It's comparing wis vs. hp for pure mana pool, which is wrong. Your HP pool does not give you more mana innately, it gives you more mana regen which is more important. Mana pool is pointless as soon as you don't have a full bar of mana, which should be any time you're actually fighting anything. A large pool of HP means that canni costs less HP %, allowing you to canni more often, improving mana regen.

It mentions that you regen mana faster while medding, which shouldn't be a consideration for any shaman above level 23.

And most amusingly, it suggests that you should ask other druids/clerics to heal you, instead of managing your own hp/mana responsibly. Embarrassing advice.