Engineering will definitely experience layoffs. Maybe not the 3/4 that the rest of the functions will experience, but likely 1/2.
I was at Broadcom for the CA Technologies and Symantec acquisitions. They laid off 3/4 of employees over 2 years not because of redundancies, but because of strategy. The butcher cares about profit and cash flow, not innovation. Products where customers have a difficult time moving to competitors will be leveraged as anchors to push the other products in the portfolio on customers with advantageous enterprise agreements and pricing. Then engineering and roadmaps will be gutted to work almost exclusively on RFEs and sec/bug maintenance to cut cost dramatically and increase profit. Because it's very difficult for customers to migrate to competitor solutions, they don't move right away, so profit is maximized for an extended period of multiple years.
Then as customers buy into the broader portfolio because of advantages in access and pricing, they lock themselves in even further. When customers are sufficiently locked in, Broadcom raised prices dramatically. Price increases account for all of their "growth". They didn't care about landing new customers. Just getting existing customers locked into the Broadcom ecosystem and then ja--ing up prices. And then they'd acquire yet another company to add to the portfolio with common customers and claim growth because they have more share of existing customers spend, further increasing customer lock-in, and justifying cranking up prices even more.
Based on his presentation, butcher pretty much said he will implement the same strategy at Citrix. So no need for as much engineering if all they're working on is RFEs and KTLO. If you survive, you'll probably be compensated pretty well. But 3/4 won't survive.