As far as I understand it is for questions regarding different "theoretical models" of quantum computers like "topological", "adiabatic", "unitary-circuit", etc. That question however doesn't seem to ask about any specific quantum computing model(s) but a general question asking "Can quantum computers handle big data?" So, should that tag be used on that question, or not?
Theoretical Models are unrelated to how data can be stored (which is the question in the question in question1, If I understood it correctly).
Either way, it fits neither the title of the question nor the question sentence in the post, both of which relate to storage and memory in quantum computing (not necessarily quantum computers).
For these reasons, I think the tag doesn't fit.
1 I did that on purpose.
As the question's author, yes.
The main reason is that 'data' is not something that can be ignored in theoretical models in the classical world if there is a lot of it. When dealing with 'big' data, i.e. data that never fits in main memory, a different model than the RAM model (which states: data access is $O(1)$, don't worry about it) is used, that takes limited space of the RAM and swapping it with parts on disk into account.
Hence, if quantum computing is to handle 'big' data, the data must be part of the model. Perhaps quantum computing isn't far enough to model data access as such, but that is a property of answers, not of the question.
So, I very much intend to hear about models as well as their implementations. If you think these are two questions, then I might split them. But for the question as stated, the tag is relevant.
I don't think that the fact I don't single out any model means the tag is inapplicable, see Which theoretical models for quantum computing are polynomial-time equivalent? for another question with the tag that doesn't single out a specific model either.