Pros
Imagine being stranded in a 1980s video game? Yep, this is that place. If you want a 9-5 job until retirement (or the bank ceasing to exist) with good benefits look no further. Most "old timers" have been here 20+ years. There are even employees here who've been around for 40 years. Some don't even know how to use Excel. The bank spends millions on contractors and consultants.
Cons
See the "Pros" section. If all you have is old timers who have little incentive to change how things are done, then you have one or two options - wait for them to leave (which they won't given the ridiculously generous pensions) or you leave. It takes an IT "field" technician 4 days to come to your desk to fix a problem with the browser. If you have no ambitions, don't want to learn anything and bide your time, come here! In a few years you'll be unemployable elsewhere. You too can become one of the old timers. If you do want to make a lot of money, come in as a contractor