Bitcoin is deflationary as it has a capped amount of coins 21mil. Supply is limited to this amount. As demand increases it will push prices up because of this fixed supply - in the long term.

When interests rates rise and the price of commodities increase people and companies are discouraged from borrowing and generally the whole economy has less to spend. Thus people and institutions are less likely to spend money on high risk assets like Bitcoin driving down demand during this period of high interest rates. Thus price decreases.

But yes in the long-run a Bitcoin will increase in value - deflationary. Whereas other fiats will ‘lose’ their individual value over time - inflationary.