but if you make a youtube stunt that hurts nobody you can get 20 years in prison and the FAA acts like you besmirched the stellar reputation of the aviation industry.
It's rather irritating. The law was made with a flexible range of punishments to permit the judge of any particular case to use discretion when determining an appropriate punishment. The maximum permitted is thus rather high. So now every article written about the subject lazily cites "up to 20 years", and thus everyone reading those articles gets the impression that he's actually likely to get 20 years for this incident.
And when the court does sentence a person for a certain offense, it should compare the specific facts of the case to the worst possible case, the one that would warrant 20 years, and if this is somewhat less than the worst possible case, then to sentence them to an appropriately shorter term.