Pros
Arm is a great company with a really strong future. The new leadership team is talented and moving the company in the right direction and an IPO is just around the corner. The work that the company does is at the forefront of the tech world. Arm pays decent (if not stellar) salaries and has generous short and long-term profit sharing schemes in good bonuses and RSU grants.
Cons
In a lot of orgs, Arm pays lip service to important things like DEI and enabling people to show their value etc. There is, in some enabling functions, a real micro management from the top and a very reactive way of thinking. In these orgs, process is more important than outcome, and the focus of the process appears to be ensuring you can blame someone else when everything goes wrong. One of the Arm values is "We, Not I" but this is seriously lacking in some areas ... to the point that you could describe it as a bullying culture in some situations.