Quite so, this is rather the point of doing Brexit in the first place

The UK’s regulation of The City should be whatever is best for the UK:

City heavyweights rowed in behind Bank of England Governor Mark Carney and former Chancellor George Osborne by calling on the UK to distance itself from Brussels after Brexit.

The UK should “move as far away as we can” from EU rules without losing access to European markets, said Nigel Wilson, chief executive of FTSE 100 insurer Legal & General.

This being rather the point of it being our government, it rules us and it should do so in whatever manner is best for us.

The benefit of access to The City’s financial markets is something that accrues to the Europeans who gain that access of course - it is the consumer who gains from trade. But even if we’re to think about the value to the producer we still want to think about this properly. Following EU rules and regulations would harm our own domestic economy by how much? And limit our exports to other non-EU jurisdictions by how much?

The entire point of Brexit itself being that we can, once again, make such calculations and take such decisions. Diverging from EU regulation is not some problem with the process, our very ability to do so is the point of it.

Whatever decision is taken may or may not be a good idea but that we can is the benefit of leaving.