Well, unless it hasn't been reported, all I have been able to determine as far as consequences that this young man has faced is one years probation, $100 fine and I read elsewhere a compulsory donation to the local burn unit. I haven't seen anywhere that he's been placed on any no-fly lists. Maybe he has been but I find it hard to believe that would be omitted from news reports.
As far as "punishments" go, for lack of a better term, they do need to meet/match the severity of the act. Now I'd never advocate locking people up and throwing away the key ( the harshest penalty we have in this country) blindly for all circumstances but at the same time there are more stakeholders involved in this crime, in any crime really, than just the principals involved. Firstly, all actions have consequences (good and bad) and it's important that perpetrators face the consequences of their actions, it's how we learn. It's also important for all of society to witness that severe and, let's face it, potentially exceedingly dangerous actions face very serious consequences so that we can have the faith that processes and procedures in place for our safety and protection are indeed working and adequate. I certainly don't get that from this incident and how it was handled. Lastly, it's important that safety authorities are given the tools and abilities necessary to carry out their mandate, which in this case is the overall protection of those who travel by air, and that the mandate for security is carried out consistently. On that last point, this situation has also suffered a major fail as far as I'm concerned.