Damien Thompson calls it a "Scientology look." I can see that. Here are some other possibilities:
1). The designers are big fans of Star Trek (perhaps they helped design this "Catholic chapel"?)
2). They mistakenly thought the event was titled, "A Billy Graham Crusade for the 21st Century and Beyond!"
3). They wondered, "Why should Protestants have all of the ugly churches?" (Not knowing, apparently, that Catholics have been building really, really ugly churches for quite some time, thanks.)
4). Someone said: "Hey, I hear the Pope is really traditional. So why not design something with a look that hearkens back to ancient times—say, the late 1970s?"
On the plus side, I don't see any felt banners...