Ahh, it was only a matter of time.
Unfortunately we can't stop people from creating wikis. Yes, it would be super if everyone contributed to the same one but this is the internet and ideals are a rare thing. That said, I see no reason why they could not be approached.
Wikia is actually a very good platform for independent wikis but the price you pay is lack of control on things such as ads. But the key thing to remember is that it's all running on Media Wiki, as it is 'the' wiki software. Wikia just adds a shell that makes it possible to build communities on any given subject very quickly, obviously the Technic community is already established, so doesn't need any help with that.
I may just make contact with the founder and see what he/she has to say.