I have a very complex spreadsheet in progress that has 37 sheets, most interlinked. There seems to be an overabundance of white space preceding and following the sheet name itself. As we can adjust the height and width of cells to bare minimum it would be useful to be able to do the same with the names of the sheets as well.
Chosen names should never contain whitespace. (When sheet names were allowed to contain spaces and/or special characters this was a very bad idea.)
If you are talking of the way the sheets are labelled on the tabs: There is no way to change that. If you intended a feature request, this is not the right placce. Go to bugs.documentfoundation.org in this case. (Bugs and feature request are both treated there. However, there may be a few million more urgent issues.)
Good design of spreadsheet documents should not include a growing number of sheets.