I have no basis for this , just conjecture based on what I’ve seen. AS is a massive business but also very automated for custody work so it tends to be profitable. Funds Services is not profitable but BNY has the scalability to do clients’ back office work for a lower cost even if it’s eating into margins. If they only keep custody, I can easily see State Street, Citi, NT, etc aggressively bidding to poach clients as no other firm wants the headache to onboard all that fund services work.
The other LOB seem almost forgotten about but if they get rid of them over the next few years, overhead can really shrink.
Just my thoughts. Feel free to add your own!