New industries will have to spawn from generative AI for there to be a net positive. Most IT and tech jobs are lower level coding positions. This will all but eliminate these roles. SWEs especially top ones will likely be safe. But that doesn't solve the societal problem.
Regarding layoffs - we've barely touched the surface. We haven't even entered recession yet, and a financial crisis looms. Most are on hiring freeze now and just in the last 2 weeks both meta and amazon slashed additional jobs. More will be coming. The industry won't completely collapse because it's a mature industry now - FAANGs are now like Coke. Blue chip. This says nothing about its workforce though - there's nothing these companies would love more than to be able to reduce the cost of their software devs.