Yes, but there's also the fact that, in certain situations, pasture and forages can cause health problem too, .....grass tetany, bloat, nutrient-deficiencies, parasites, nitrate poisoning, prussic-acid poisoning.....etc.There's MUCH to be considered when comparing cattle feeding methods and nutrient regimens and doing what's best for the animals. I grew up in dairying and worked a seasonal pasture-based dairy (plus beef) for several years...i'm ALL for it but there's a lot of popular and related "feel good" information, perception and opinion that's just plain wrong.In terms of good beef, good genetics is paramount, some cattle won't yield good beef to matter what they're fed!!!
Right, with horses these days I know people who have taken college level courses about equine nutrition in order to make sure they are feeding the animals in their care correctly, and have testing done regularly on the local grass and on the hay they bring in (to supplement the pasture - some areas don't support grass enough of the year for horses to be only on pasture, or the type of grass that will grow is not nutritionally complete, etc. Various reasons for feeding hay even if there is ample pasture.) And many of these folks are just people trying to provided good care for a companion animal, not people trying to make a living in the industry.
Given that, I can't imagine that how to feed up meat livestock like cattle is any simpler a proposition - your livelihood depends on the animals maturing as expected into acceptable quality meat, without having too many problems along the way which require vet care, since vet visits cut into the bottom line. (Note I am not saying people would not get cattle care, just that it is in the best interest of the farmer or rancher to manage things in a way that reduces the chances of needing extra vet care beyond the routine stuff they can budget for in advance.) Then you add to just wanting to keep them healthy the idea of finding a market niche by being able to reliably produce a certain characteristic in the meat, which often occurs due to diet, and you end up with a situation where I am sure a good cattle farmer could talk your ear off about feeding options for beef cattle, and which you would choose when and why.
Don't get me wrong - I do think we need to get away from factory and intensive farming methods where subpar care is corrected by just giving the whole herd antibiotics and other similar interventions - I much prefer my meat to have had a decent quality of life before it ends up on my plate, and an environment in which medications are required because the keeping method itself basically makes the animals sick seems pretty unlikely to be a good quality of life situation. I just doubt that good care and keeping practices for all herds in all places are the same in terms of what they need nutritionally, be it grass or grain or hay or a commercial feed product.