Not sure what world you live in, but the vast majority of new people interested in Bitcoin are interested because they want to make money, not because they believe in the technology. They want to buy in, see it go up 500%, and cash out.
They're not motivated by the actions of the central banks, they likely have no idea what the central banks do. They see "Bitcoin increases 100% in a day!" on the news or on a website and want in on that sweet money making. Coinbase makes it so easy, they have to do absolutely minimal research, don't even have to wait for transactions to be confirmed.
You think its lack of faith in the current banking system and belief in the new tech that's driving the price up as high as it is now, when it's mostly greed and ease of access. Taking that into account it's naive to not believe there is a Bitcoin bubble.