I think the markets have already priced this in, so there will be basically no reaction. Zuck has more or less announced the cuts already.
"but ... why?" they have a ton of talent because they pay top of band and they staff their workforce with great employees. Great talent wants to be paid well and wants to work with great talent, meta has both.
For what its worth, meta has more employees now than they had in Q1 2022, and these next rounds of layoffs put them at staffing levels of like Q3 2021. The reality is that Meta and other huge companies grew headcount faster than revenue, and need to unwind some decisions they made.