It is not a case of blaming landowners, if we want to understand the underlying causes then it is necessary to identify the interests of the different parties.
As a farm manager I bred and milked daily a variety of cattle breeds. Bred both pedigree sheep and commercial fatstock, with some experience of flying flocks. From your many many years of experience, have you noticed, the current trend to grass fed beef is reducing the daily high protein rations being fed. Also the actual relationship of human contact with cattle was infinitely greater, when cattle went into cowsheds to be secured by neck chains on a daily or twice daily basis.
Now this was done before the days that the term 'Risk assessment' became a managerial norm, but temperament of individual animals was known and dealt with in a manner appropriate to the times.
Members of the public are not made aware of how important their observations are and this is because there is the massive reduction in the rural population, who work on the land. Landowners would prefer that they are not there and this is because of self interest unrelated to agricultural production. So they repress any collection of data that might jeopardize their self interest and might be of benefit to the workers in the rural enterprises as well as visitors.
More could be done in stock management to safeguard visitors, why not create safe zones around entry/exit points, temporary fencing equipment is light, effective and very mobile. Risk management has advanced beneficially in so many other endeavors, so why is it not advancing in the countryside without penalizing the visitor. Is it the interests of the agricultural producer or is it the interests of the landowner that is the root cause?
I think it is necessary for both organizations, which represent each separate issue to come clean.