From what I can observe the companies are more about reducing travel rather than changing policy. I know quite a lot of companies and their policy is still the same like 10 years ago, which is in general picture I can describe as: no C-class for regular workers and low-management level, mid-management C-class for long haul only, upper management C-class; F-class (except US domestic) prohibited for all, biz jet or charter only when really justified.