TWO RESTS FOR TWO VOICES?

If you look In staff properties there is a “Merge matching rests” option. Default is off.

Are double rests acceptable? Yes, sometimes, sometimes no. If you are writing counterpoint, you probably want the separate rests, if not, probably not. But having them separate while editing is useful as it is difficult to select one particular rest from a merged pair. Merge them when you have finished editing but before you start tweaking the formatting

See also this Github issue for more discussion on this topic. github.com/musescore/MuseScore/issues/24983