Start fixing it in Openstreetmap yourself, or even better, get in touch with active OSM mappers in Utah, and talk to them about this.

OsmAnd merely makes use of the data from OSM.

Is it an OSM or OsmAnd issue? Does it work on osm.org?

I'm not sure if supporting local slang formats for addresses should be very high on the list of priorities.

Assuming "slang" is an exaggeration: the basic principle of OSM is that things are mapped and named as they are on the ground. So local names and naming conventions should work; if they don't, it's a bug.

what the fuck? can you share some examples?