I don't know if you meant from the consumer perspective, but if my bank started telling me what kind of a phone or computer I needed to have to use their servic

I don't know if you meant from the consumer perspective, but if my bank started telling me what kind of a phone or computer I needed to have to use their services I would definitely find another bank! I'm not sure if clout is the right word for what what banks have, it's more like a kind of lock-in because of having to sign a million pieces of paper to change banks, that makes people put up with a certain amount of IT inconvenience, coupled with the fact that usually the competition is equally inconvenient.