Another dose of sarcasm and misanthropy from windmill.
Curate just means to select, organise and present.
It has been used since the 1800s to refer to museum and gallery collections e.g. someone has curated a collection of Roman artefacts or pre-Raphaelite paintings for others to see and enjoy.
For the last 25 years or so its use has been extended to collections of other things that one person might present to others. It might be a restaurant menu, a collection of programme on TV or content on a website e.g. someone working for GN has curated a collection of features on health, skin care, diet etc that they think will be of interest to the site’s members.
It comes from the classical Latin cūrātor meaning keeper, supervisor or overseer.
I don’t see the problem or why the horse is laughing - unless he’s sitting in front of a screen watching a curated collection of cartoons, TV shows and films about horses. Mister Ed maybe.