“Pretending” is part of having manners. But irrespective of that, he doesn’t have to “pretend” to be happy, he just has to be a decent human being and do his job. That’s the thing about jobs, you don’t only get to do them when everything is great.
Anyone can be a good winner, especially in a crap conference. But, speaking as a long-time sports journalist, it is part of HIS JOB to conduct a reasonable media conference, win lose or draw.
And when you have quite purposefully developed a reputation for being the happiest player ever — dancing after first downs, etc. — and built yourself into the face of the franchise, with all of the rewards that go with those things, acting like an adult for 20 minutes after you played a terrible game against an awesome D isn’t too much to ask.
Just do your job.