Interest expense is 64m in the trailing twelve months so it's not a meaningful difference in their cash burn. Most corporate debt is fixed rate and with a net cash position they don't need to roll it over. Interest rates affect Twilio by affecting the economy.
The fact that revenues are not rising as fast as management expected means the only way left to reduce losses is to cut expenses.
Twilio's debt to equity ratio is small enough to be irrelevant.
Revenue is falling while the economy is still growing because pandemic trends are reverting to normal. Same as e-commerce, which caught Shopify and Amazon with too many employees. Same as media, which caught Netflix flatfooted.
People are shifting their spend from goods to services and from online to offline. Coincidentally, that's what people use to explain inflation. There's always micro trends underlying a macro trend.
The fact that revenues are not rising as fast as management expected means the only way left to reduce losses is to cut expenses.