Because trust is what drives the price of BTC. Now coming back to your query about how BTC could be impacted by Economic situations, I must say you should ask a question first as a prerequisite, which is; how do people react to economic events and vice versa? If you (people) see an economic event that is good for the market they will trust it more and boom prices are high again. And if any economic event is found bad for the market by users then trust will also crumble resulting in a Downfall of the BTC price. This is the simplest explanation to your query not doubt the factors of economic effectiveness on BTC's price are numerous but I tried to mention the common one which (factor) is driven by all the other factors.
Talkin about SVB people started to withdraw their assets from the bank once they saw the liquidation conditions of it. This news and information act as a factor that plays with the trust people have in SVB that affects all the other markets. I made a post about how the bank's downturn affects BTC price this could also help you. (Note* this hyperlink post is not about all the banks but logics is same)