When you print an additional 2% of the money supply, you are essentially taking about 2% of the entire economy and assigning it to yourself.
Back when money was gold, and gold was money, in order to increase the money supply by 2%, you had to mine 2% of all gold already in the marketplace, which required a lot of labor and capital. If the price of gold was high, you worked more expensive mines. If it was low, you idled them as temporarily unprofitable. The effect of the increase on the money supply was diffused throughout the economy by virtue of the sheer amount of work required to accomplish it.
With paper money, all that is required is a press and anti-counterfeiting measures. The transfer of value into the new money is far more concentrated, both in terms of actors and time. The buying power of the new money is higher, because people don't necessarily know how much you printed until you start spending it.
It is a great virtue for Bitcoin to make public the exact amount of new money added to the economy. Monetary inflation can therefore be predicted exactly. It's still inflationary, and does not account for changes in demand to achieve a stable money price. What it needs is a feedback loop that connects mining rewards with demand for the currency. I imagine that could key from the hash rate of the whole network, but I'm not certain how.
There is no basis for the assumptions about demand for money vs. other goods that are necessary for this to be a justifiable claim.
Assumption: The money itself has zero intrinsic value. It is only worth what you can trade for it. Thanks to the previous assumption, that is a fraction of all goods and services on the market.
When you change the size of the money supply from 100 to 102, the 2 new notes increase in value from 0 to 1/102 of everything on the market, and all of the 100 old notes decrease from 1/100 to 1/102 of everything. The guy that prints the new notes gets 2/102 of everything for free. That value is not created; it is taken. Everyone who held any old note has their buying power reduced by 1.96%.
Is it justifiable? Yes. Is it a gross simplification because economics is a dismal, dismal science? Also yes.