Bitcoin is inflationary too and it pays zero interest.
The number of bitcoins is capped at a distant future date; but in the present, it continually increases. This is similar to how a curved Earth can appear to be locally flat. For now and for many years to come, the supply of bitcoins does inflate constantly.
Inflation is a measure on prices, not money supply. Bitcoin’s money supply is increasing. It is, on average, deflationary.