Well considering that's one of UK biggest sectors, then yes it is.

The UK economy is disproportionately based on global finance, so it's a bigger deal than it might be somewhere else.

There is more than 50 companies in the UK. what should be news is companies that are not moving at all and staying in the UK during the storm.

It's cherry-picked, although I'm sure some more companies are thinking along these lines, but aren't as vocal.

A list of big companies that have committed to staying would genuinely be useful. I doubt you'll find many, since saying something like that before there's a clear deal is a bit irresponsible, like a blank cheque.

Only if you don't use banks or insurances.

Financial services is a huge part of the uk economy, so banks are quite a big deal.