I didn't have a traumatic upbringing, as it happens. That was my mum's first husband.
My dad is the proverbial man who wouldn't hurt a fly. Literally. I learned a lot from him about valuing ALL life. He is honestly the most ethical, moral person I know. He literally cannot conceive of making an immoral choice - ironically he'd hate a debate like this!
(I'm no such paragon)
Yes, I know that cats are killers. But I don't begrudge humans killing either. I am a meat eater, after all. I don't begrudge cats a bit of genetic predisposition to murder-based play. I accept that there's less malice in cats and dogs because their emotions are less complex.
What I don't accept is the flat application of complex intelligence as a virtue. Or anything as an assumed superiority. For one big reason - if it's OK to decide that some animals are better than others because they're more intelligent, then what is the logical bar to preventing humans from being assessed and ranked in the same way?
If you say that you are ranking on emotional and intellectual capacity, then why isn't a bomb sniffing dog who saved his master's baby from a fire and who acts as a comfort dog to children with depression more valued than, say, an inbred man with an IQ of seventy who is a paedophile?
Like I say - I value people and animals who are affectionate to me and give me service or provide me with benefit. I think that that is the honest, rational answer, and to be honest, that that is what it comes down to for most people.
Except, perhaps, my dad.