Is not there any attempt to improve the soft deletion at the engine/SQL level? I can see it as a possible feature request.
The information schema table holds all foreign key relationships, so one can write a generic procedure that cascades through the fkey graph to soft-delete rows in any related tables.
It's not a standard (I think) but it'd let you do a cascading delete and then be able to go and look at the old objects as they were at time of deletion too.
You'd need to do things very differently to show a list of deleted objects though.
They were introduced in ANSI SQL 2011.
How closely implementations follow the standard I don't know, but something close exists in several DBMSs: I use them regualrly in MS SQL Server, there are plug-ins for postgres, MariaDB has them, and so forth.
However in practice this usually dramatically slows down reads if you have to constantly skip over the historic rows so you probably don't want to keep garbage round longer than absolutely necessary. The concept of a historic table mentioned below could be interesting though - especially if it could be offloaded to cold storage.