I used to think similarly, but now I’m not so sure. Gabe Brown, the author of Dirt to Soil, changed my outlook on animals place in a healthy ecosystem.
On his farmland he puts about 700k lbs of cattle on 1acre of land at a time, rotating those cattle frequently across 40 acres. He claims this practice has been an integral part of his regenerative ag method.
> A large-framed cow is one that requires a higher intake level for maintenance alone
https://brownsranch.us/livestock/
My math came out similarly to yours but I don’t think it’s unreasonable for there to be 150lbs of waste high cover crop biomass in a 6 square meter area.
Again he is rotating these cattle daily and never depleting the crops of any one area, giving them a chance to grow back by the time the cattle are rotated back through.
Another term you can search for to find visuals of what this sort of density looks like is mobgrazing.
[1] https://www.thebeefsite.com/articles/3154/how-much-forage-do...