It is completely relevant, but you seem to want to ignore actual facts.  

Since it seems like the seller obviously knew about this and never disclosed it - and the seller's agent at the very best was ignorant about it - does it make sense to sue to recoup these losses? 

These people just need a little help and you can either offer it for them, to them, or ignore it.

Welcome to BP.If you're starting out and looking for places to invest I'd recommend ignoring downtown/midtown.  

Normally the rehab consist of fixing the things that are broken, laying some cheap carpet and vinyl flooring, then ignoring all the deferred maintenance items.

As a general rule of life for myself, I ignore advice from people who offer it after telling me that they don't like what I'm doing.

If you are buying somewhere else ignore my input.

Ignore her till 30 days notice is up then do as you please.

Ignore the "white haired disabled old lady" emotional noise.

#FirstWorldLenderProblems, the good ole "I just went into escrow and I didn't realize that getting a mortgage requires my active participation and I'm going to ignore my realtor telling me to cancel our vacation plans," our favorite.