I was checking out the competition for a new niche I am considering entering. I checked the Domain Authority and Page Authority of the Top 5 sites, and they all had very low metrics and only a couple of backlinks. None of the links were PBNs. This seemed strange to me, as I figured this would have been a much more competitive niche (lots of $$$ to be made). So my question is, could these sites all be using PBNs to rank but have bots blocked by plugins such as Spyder Spanker or Link Privacy? Would that cause them to rank high on page 1, even with low site metrics? Or does using PBN links still increase your DA/PA metrics regardless?