Hey @reggaemuffin, much respect!.... My point is to "VALUE THE SBD", don't think in terms of converting to BTC or USD. That is a short term perspective., based on "what is it worth now". Think in long term perspective. Think in terms of wanting to hold STEEM AND SBD, Not trying to convert to BTC or USD.
Concerning your pizza/crypto example... if the pizza has a set desired USD price, and the crypto currency drops 25%, then yes, you have to raise prices 25%, and the prices have to be dynamically determined based on the current crypto currency price. This is just math and expected. This is because you value the USD price before your value of the crypto.
However, consider an asset that is based strictly on a cryptocurrency. Let's say a service sells monthly service for 10 SBD, without concern for the 'so-called' USD price of SBD. This service price of 10 SBD does not change.
This is why I keep saying "VALUE THE SBD!!"