Ok correct me if I'm wrong but only those who are worthy may WIELD it, as in use it so the rule of being worthy probably doesn't apply to objects cause if it did the table and floor would break under the hammers weight
I like to say that the welder of mjolnir can give inanimate objects an honorary worthiness so the coat hanger and the table in the lifting attempt scene are worthy
If the coat rack is worthy then you would have to say the table from endgame or infinity war was also worthy because the hammer was put down on that while everyone was trying to pick it up
I don't think improving really counts as bloopers. Since a blooper would essential have to be an accident and improv is often done on purpose. Especially considering that the majority of Ragnarok was improvised. And many actors like Robin Williams and Jim Carrey improvise like it's breathing.