To get around this will companies just extend their runway with a line of credit or some other form of debt?
In these cases, companies raise funds at the same valuation as their previous round, often labeled as Series A+ or Series C+ or Series B Extension.
Another, less common strategy involves using a SAFE (Simple Agreement for Future Equity), which will convert to equity during the next priced round.
I have to imagine this priority shift is in part due to the money markets being what they are.