Some of the technical complexity comes from the sheer diversity of data sources and sinks. The infrastructure is also non-trivial.
This is somewhat future looking because most large startups have a data team that builds their own in-house system eg Airbnb, Yelp. However a lot of companies don't have that luxury and extracting value (patterns and insights, for example) from your data is useful for many businesses.
That's right! This problem is so hard that NOBODY can claim to have figured it out. And I haven't even gotten to the market size--the potential market size is literally the entire humanity! Not everyone wants to share what they had for lunch, but EVERYONE wants to get laid!
Hope this answers your question!
The harder problem is getting laid and feeling some dignity afterwards.