I mentioned that in another thread, but banks have a legal obligation to to assess and mitigate risks in the service they give to you- you, personally, might be tech savvy enough to understand what you are doing but most people are not and the bank is held accountable when something bad happens.
This is why they limit service to certain devices or OS versions, even when it comes at the expense of convenience.
> legal obligation to to assess and mitigate risks
It's obviously not about risks. It's about convenience on their side to only support 2 platforms and call it a day.
Perhaps the solution then is to invent a new bank that is more resistant to regulation and gives users more freedom to secure their own funds.