Lucy Kellaway answers the questions of FT-readers
The reason all this seems so sinister to you is that you are one of the few survivors from the old regime, which means you naturally distrust the team coming in and resent their clannishness.
This is not unusual
You complain that morale is low. This too is natural. Yours is low because it is wretched being in a minority, and others' is probably low because banking has been in crisis. If morale were sky high, I would be even more worried.
You say he abuses people, but even this is not unusual. Plenty of good CEOs are bullies - the answer is to keep out of his way and if he lets rip at you, not to take it too personally.
Nothing you can do
Despite the above, it is perfectly possible this man is unusually horrible and is making ever poorer decisions than others in your sector. If this is so, there is absolutely nothing you can do about it other than bide your time and know that he will get found out before long. And then you will have another new broom to get used to, who might be as bad as this one - or worse.