Low barrier to entry can do a lot. Regardless, a much more important factor is that all the data about everything, which people have been collecting for decade

Low barrier to entry can do a lot. Regardless, a much more important factor is that all the data about everything, which people have been collecting for decades as a matter of almost religious belief in its usefulness and never done anything with it, is actually going to be used now, for better or worse. "Targeted adds" of today will look like a joke compared to that.