>>> Today it might have 100x that. So, how many compliance people will Google have in five years?

Compliance goes hand in glove with regulatory reporting. Reporting to regulators should be a marginal cost thing - if the data internally is same, well managed and fully auditable in an automated fashion.

Doing this in finance is something the new challenger banks (ie monzo built about five years ago by ten coders and now has a million UK accounts) - this is something they can have one compliance person because all their systems are new and written with compliance in mind.

Doing this for most major banks is next to impossible. It would rewriting everything (#)

(#) Actuallly i would say this is a good strategic plan for most major banks. Might not be able to persuade the board but still.