I think I disagree; “tolerance”, to me, seems to point more towards the special case where {B} is some external events and {X} and {Y} are internal reactions. To talk about social affordances, as the OP does, you’d have to talk about the tolerances of others for {B} done by different people [A-E] -- and you’ve made less obvious the fact that the tolerance of [Q] for {B} done by [A] is different than the tolerance of [Q] for {B} done by [E] -- the entire content of the post.
The term “affordance width” makes sense, but perhaps there’s no need to coin a new term when “tolerance” exists already.
I think I disagree; “tolerance”, to me, seems to point more towards the special case where {B} is some external events and {X} and {Y} are internal reactions. To talk about social affordances, as the OP does, you’d have to talk about the tolerances of others for {B} done by different people [A-E] -- and you’ve made less obvious the fact that the tolerance of [Q] for {B} done by [A] is different than the tolerance of [Q] for {B} done by [E] -- the entire content of the post.