I don't "recreational climb" but feel confident to offer some feedback since I climb around in a lot of trees for small scale pruning, plus understand forests, trees and soils better than most.
For guidelines and instruction, it's important to hold neutral ground and not support an agenda. Just the facts and common sense.
Some statements like "will impact or damage the roots of the trees" are not necessarily true. That could be phrased "may impact or damage the roots of trees". In summer, soil may be so dry that compaction is virtually impossible. Sometimes when it's dry, a dump truck could drive over and not cause a problem. It boils down to where the tree is, whether you are the only person, and how moist the soil is. Or whether sensitive roots are really vulnerable. Which, honestly, rarely get damages if only one or two people are around the tree.
In some ways, it would be higher level of ethics, to gain instruction in that regard, by an arborist or horticulturist who is completely fair and balanced about the matter.
Its good to err on the side of caution, but if absolutes and guidelines lean extreme, people with common sense will ignore them, and the disrespect will just ripple into other areas.
Regarding avoiding nests and wildlife, I encounter that difficulty even in arborvitae hedges. Virtually any tree can have a nest in it. And someone erring on the side of caution may need to avoid every tree. But another option is learning which months birds and wildlife build nests, then avoiding climbing those months if the entire tree isn't open for easy observation first. With hedges like I mentioned, I try to avoid heavy pruning spring months and encourage people to wait for autumn, or get it done sooner January to March.
Do TCI folks have local lists for wildlife in certain trees or forests?