Since currencies are no longer backed by gold, a national bank, f.e. the FED, can print as much money as they want. However, an excess of available money of course leads to its devaluation on the markets.

Nevertheless, there will never be a huge availability of VC money. There are just more easy ways to profit than high risk investments.

And no, no one is gonna back just every idea, that would be silly and lead to nothing.

I think access is also based on perception only. If you think an idea will work and if you believe it can, you'll invest. No one can be sure, it's still a little bit of gambling. As an entrepreneur, you gotta know how to sell your idea, perception counts...