why focused niches will not overcome generic blogs?!

with a narrow focused niche your keywords span is low and any chances of attractic natural traffic from Google searches will go also very low! So better write wathever you wosh using the SEO crap! thos crap evolves anyway and it should better keep up with publishers work and not the other way around! whoever nvented that SEO crap was a poor search engine writer that wanted to rule the Internet world!