The question regarding should big tech be prevented from offering banking services is too broad. I can only opine regarding certain banking services with a lot of ‘where as’ and ‘what for’ disclaimers. First, any banking service needs to have the same regulation and oversight as any traditional banking service irrespective of who offers it. Crypto currency services, if offered, needs clear rules and regulations regarding it’s use no matter who offers it- financial services or tech platforms. While the ability to rapidly exchange funds is attractive, the anonymity currently afforded crypto currency transactions could easily be abused by foreign governments and illegal enterprises. I do not want to ‘institutionalize’ money laundering by tech companies or banking institutions until the anonymity aspect is removed. Putting these services on broadly used social media sites is way too open to all kinds of abuse and if readily and broadly available, could be used by adversaries as a tool to destabilize financial markets and the overall economy. In terms of simple transaction services like credit card transactions, bill payment or gifts of money expedited by big tech platforms- I see very little to be concerned with since the banks and underwriting credit card institutions have rules, regulations and oversight, and have records of what went where and when. Finally, the access to personal data which could be abused is a big issue and the misuse of personal data collected by big tech platforms or big bank institutions should be punished severely, even if such use was ‘accidental’. The transfer of personal data from big tech platforms to big data operators supports one of the biggest hidden industries in existence today which generally knows more about each of us then we actually know about ourselves; they buy this data from a variety of sources, digest and compile it, and sell it to anyone interested in monitoring or influencing you or I individually or people within highly selective demographic groups. The trump campaign hired Cambridge Analytica which used Facebook data and big data sources to develop psychological profiles of voters in key electoral college swing districts, to use proven military grade psy-ops targeted messaging to influence select voters in order to capture electoral college votes. I think that penalties on the sale or purchase of such data is needed and that any platform which accidentally or intentionally abuses their stewardship of personal data should be severely fined and barred from offering banking-like services of any kind for a period of say 5 years- and that any tech platform that has accidentally or intentionally abused their stewardship of our personal data within the past 5 years should not be permitted to offer banking services of any kind. In short, crypto-currency: no until anonymity is removed. General bank transactions: yes , if proper stewardship of personal data is demonstrated and is not abused.