Thanks @bcarlsonmedia.
Tech is always so quick to "create" programs that bulldoze content, then ask for forgiveness or pay a token bag of shiny beads afterwards. Both approaches I've long held as inadequate and typically should cost them dearly.
A search engine is doable for a niche. Freely slurping all the content, well site owners probably will complain loudly as it taxes resources.
Highly advise limited scope to test whatever you do start --- like to one site like vpsBoard. Get that working with data set then expand.
My gripes about aggregators come from years of having content stolen, reused, chasing idiots over it and finally just saying screw it. I won't even go into the mess search spiders can and do create. Wild West still persists.