Is hoarding a problem in the Bitcoin world?

The simple answer is that hoarding is not a problem in the bitcoin world. The reasons are:

1.) Bitcoin value is calculated to the eighth digit after the decimal
point (the hundred-millionths), unlike cash, which is only
broken down to hundredths, or cents. For example, trading in
U.S. dollars allows you to charge $11.99. Bitcoin would allow
a charge of 11.98765432 BTC. Although this may not seem to
be of significance now, should the value of BTC exponentially
increase in the coming years, those additional decimal places
will be very useful for accurate pricing in the future.

2.) Bitcoin volatility is affected mainly by the laws of demand and supply. The higher the demand for the liquidation of BTC in an exchange (E.g Coinbase, Kraken) the lower the price of BTC in the exchange and vice versa.

3.) Bitcoins are minted every day into circulation, this systematically regulates inflation.