While I'm generally inclined towards pessimism when it comes to new technology, there is something to be said for when billions of dollars start being invested

While I'm generally inclined towards pessimism when it comes to new technology, there is something to be said for when billions of dollars start being invested in a large number of companies chasing the same dream. One could argue that these funds are being poorly invested, but that begs the question: why now? Why didn't we see this money being 'thrown away' 10, 15, 20 years ago? What's changed that those with the means to make such investments believe that now is the right time to be putting money into long shots? And so I'm left to have one simple hope: maybe the very rich people have hired people smarter than me to assess if there's a chance in hell this will work. It sure seems like a lot of people suddenly think they can do it.