If they were able to plan ahead, sure, that would be the way to go. But it sounds like a lot of the budget cutting was done on the fly...
Except the quote from the head writer says, "
Once we got into pre-production and production itself, once somebody had to sit down and start figuring out the cost of everything, it was like every week, I was told, 'Can you cut more She-Hulk scenes? Can you change more She-Hulk scenes to Jen? Can she be Jen in more scenes?'" Gao explains.
So it seems like it became known as an issue in pre-production and that should have clued them in that maybe random office scenes with She-Hulk sitting at a desk weren't worth spending the CGI budget on.
Plus, having worked at law firms, I always thought it was a super odd choice for the managing partner who hired her to expect her to be in She-Hulk form all the time in the office. Law firms are generally fairly conservative and wanting a big superhero sideshow walking around the office just seems really strange. I could see if a particular client wanted to meet with She-Hulk then she could change for that meeting, but most lawyers spend the majority of their time in the office just sitting at their desk writing, talking on the phone, etc. The percentage of time actually meeting with clients face-to-face (or even over video conference) is generally very small.