But regardless of whether any big tech co. needs loans or not, the cost of any investment they make, as well as the referred-to-present value of any payoff from it, are anchored to the interest rate. And the recent upward movement in the interest rate -- not to mention high inflation -- has drastically (relative to the ~0% interest days) raised the costs and lowered the payoffs.
Tech (both Big Tech & startups) is also getting hammered hardest first here mostly because those are the ventures that attracted investment of the lion's share of 0%-minted dollars, and that investment is vaporizing at the same time that the ROI (payoffs - costs) on lots of those firms' WIP has gone negative.
If interest rates are high, then buying something has a higher opportunity cost since you're forgoing earning interest on your capital. As patio11 put it in https://www.bitsaboutmoney.com/archive/banking-in-very-uncer..., "when interest rates rise, all asset prices must fall."
Businesses don't pay for costs solely with revenue, they also use cash from loans. Revenue is used to pay off loans, so higher interest rates mean loans become more expensive. To maintain constant loan repayment costs through a projected year, the total amount of those loans has to go down. With lower cash from loans, costs have to be cut and payroll is one of them.
I think this partially explains why everyone is doing layoffs regardless of revenue performance: they all have to adapt to the same conditions of higher interest rates.