What she actually said was:
She doesn’t want 2 acres total, and then spend all her time buying and stacking and feeding hay, picking manure daily, cleaning stalls, bringing horses in and out so they aren’t 24x7 on grass, maintaining a dry lot (with more manure picking) for the wet months, etc.
Things like fencing maintenance exists regardless, BUT, you can choose fencing that takes less time (and $) to maintain. My Horseguard tape is SO low maintenance. Grass maintenance exists no matter what, but you can spend smaller amounts of time more often mowing a smaller pasture you’re rotating out of, or spend more time less often mowing a bigger space.
As I’ve mentioned, we have maybe 7-ish acres of pasture, with 3-4 horses (currently 3, was 4 for a while) I mow the pasture, seed, fertilize, and drag, I ride, I trim their feet, I’m here for the vet. Hubby weed eats the fence line a few times during the growing season, mostly more because it bothers him than it actually needs to be done. He mows the yard and outside the fenceline. BUT, the things he does allow me the time to mess with the gardens which are a choice, not a must-have, and even they don’t take so much time I couldn’t do the work he does as well. All while working full time, both of us, away from home before covid.
If you have 15+ acres, I would probably divide into 2 if mowing for 6+ hours at a time isn’t your cup of tea. It takes me 4-ish hours to mow with a Ford 4000 and a finish mower, some of that is having to go slower in some areas, and some areas end up driving over mowed areas a few times, so it’s just not always efficient.