Exactly. My view is from someone who is not yet very proficient in coding, is starting to code or coming from Javascript world. My view is also from someone who is highly proficient but knows the future problems of maintaining a 100% updated, compliant and reliable driver outside of a core team that also handles the core ecosystem (meaning, José Valim is very active in all key parts of the ecosystem, even now with the authentication part).
I agree with a lot of what you say, but at the same time think you miss my point: I think Elixir ecosystem would unlock the doors to much more developers by "officially " supporting another option for DBs rather than just traditional Relational DBs.
I have my personal preferences, you have yours, others will have different ones. I understand that we cannot have to many “official” options, but I believe this is one of the “details” that keeps preventing Elixir to have the adoption rate that it deserves.
Looking into Ecto documentation and only see traditional Relational DBs being mentioned in there…I remember that there was a time when we had MongoDb mentioned in there. And it was because of that, by then, that I decided to really use it.
The truth is that I still use it, even without MongoDB, as I later discover that MongoDB was probably not the best option, but it was looking into that possibility when I was assessing the Ecosystem that made my tried and start using it.
So, even if it would be only marketing, or the price to pay for larger adoption, I think we should have “officially” supported options.
The larger the user base the more libraries, blogs, support, recruitment base,…you have.
I would love to see the ecosystem grow at a faster pace.
And yes, I’m being selfish but I think it’s in a good way. 
because the relation itself becomes a first class citizen (having it’s own properties). Also the query language is such a pleasure compared to SQL (much more compact and closer to the natural intent of the query).
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