All modern samsung phones will get the update within a few months so a replacement won't help. It also cannot be undone.
Also most android phones will get similar looks when android 16 releases. Android itself looks a lot like one ui 7
Service aren't being helpful because there's nothing they can do for you. If you don't like the way the ui looks, more people do like it
Are there any exact things you don't like? Usually there's a setting to change things
