It's the fault of my family organization or every company we use that my parent's bank, Google, phone, laptop, etc don't allow more than one set of credentials to access the same thing?
It's not just that we need to be able to share credentials the once a blue moon I need to help them by logging into their account?

Sometimes it just makes sense to have a single team login.
Licensing for instance where each user costs money and not all users need a dedicated account to look at something of which only 1% is of importance to them.

You know why most cloud based services charge money? For stuff like this, because it’s not free to implement and maintain.

Easy and fault-proof password sharing and syncing needs software and hardware to do. You either set it up and maintain it yourself, or pay for a product that does it - like Bitwarden.