Depends on how broad a range of styles the division is. Judges in a "northern kungfu" or just "soft style" division (if in one of those open karate tournaments), aren't going to know whether every form is a traditional form and a good judge is going to base their scores on the quality of the person doing the form rather than the choreography of the form itself. If a guy has better power, intent, speed, stance work, transitions, etc. than another person then it shouldn't matter whether the form is 10 or 100 years old. The modern mantis form is a heck of a lot less flashy than many other forms out there. Less jumping around than some traditional styles.

If there's a modern wushu division that allows non chang quan/nan quan forms, or if it's a traditional mantis only division then of course it's a different story since it's a specific modern wushu competition form. Though, it's hard to get upset when the average Wah Lum competition form I've seen had more non traditional flash added in than Yui Hai's form. Same goes for a number of other traditionalists out there.