WTH: why can't we have easily per user dashboards?

As admin of HA, I can create X different dashboards. I would like to have a way to map user A to dashboard a, B to b… Kind of a login page. And user A wouldn’t be able to go to b and vice-versa. All the available solutions (see Per user lovelace dashboard, how?) for me are unideal ways to accommodate that missing (at least for me) feature.