Many banks restrict the number and capabilities of secondary users. In the end I had to get a power of attorney, but for me observing these changes is just a warning. I see a pervasive use of a phone as means of authentication and the compulsory nature of hardware-bound digital IDs is penetrating our society. That is a barrier for elderly people but also for other groups, specially when those requirements are not accompanied by standards (i.e. why does a French person need to get a new ID to work with Spanish bureaucracy) and also because the phone itself is an unsubsidized cost. Not to mention when one is travelling to countries with locked networks, losing the phone or, closer to the topic here,the lack of trust on generic phone platforms, which enforces a duopoly (Google Android + iOS) preventing new technologies to enter the market.