I can’t speak for all other animals, but I imagine it’s often for similar reasons as why they do it for cats: removing the hormones means they’re much less likely to display unwanted behaviors such as marking/spraying, territorial aggression (fighting) towards other cats, and roaming. Those behaviors all stem from the desire to mate, and if they don’t have testosterone from the testicles, they don’t experience the desire to mate. Unless you don’t mind the smell of concentrated cat urine everywhere, adult male cats with testicles don’t make very great house pets.
With female cats, they completely remove the ovaries (rather than doing a tubal ligation) for similar reasons. If they did a tubal ligation instead, the cat would still go into heat, meaning lots of yowling and trying to escape, and an increased risk of marking/spraying, just no longer able to get pregnant. In my region, they also usually remove the uterus, but it appears that varies globally.
I’m not sure about compatibility with HA (saw this via /all), but I bought the Whynter ARC-14S and a Broadlink IR universal remote + sensor cable so that I could set up some automations and/or control the AC via my phone. I think any AC with an IR remote should work in that setup.
If you’re in an area that gets lots of poor air quality days while you’ll be running it (my area usually gets a few weeks of terrible air in August & September due to wildfires), a dual hose AC is definitely worthwhile.