I mean sure, merging back can be a huge process. But I think it’s more about that being the process overall.
i.e. you would only merge small bug fixes directly to the root and anything else is a merge from a branch. That way you are coordinating all your big mods. I take my branch and when I merge back the code is mostly as it was.
You’re doing your big mod on a different branch but at that point you then merge down from root to your branch and adjust and on the schedule you’re next to merge up to root.
It’s hard for me to really judge because we creating huge pieces of software based around big DB changes and whole sections devoted to one particular type of insurance processing so when you branch and merge back you’re often fairly isolated from a chunk of the central code processing.