Discussion "A sheet by default" on <Libreoffice-ux-advise> showed common sense to change default from "3" to 1 new sheet in new spreadsheet document. I believe it's enough to modify builds so that that default will be used for a newly created User Profile. In existing profiles default can be modified by user in 'Tools -> Options -> Calc -> Defaults'
To localize what setting it is, just copy the user configuration (like .config/libreoffice) without the change in 'Tools -> Options -> Calc -> Defaults' somewhere, change the default, and diff between the saved configuration and the current .config/libreoffice. It is a xml configuration, so in order to see the difference more conveniently, you can use eg. xmllint --format.
Stefan Knorr (astron) committed a patch related to this issue. It has been pushed to "master": http://cgit.freedesktop.org/libreoffice/core/commit/?id=9a7d3d47d9b4d57b0c7380eadb294add4245ba3a fdo#50183 Use one sheet as default in Calc
Closing as fixed, see above.
Stephan Bergmann committed a patch related to this issue. It has been pushed to "master": http://cgit.freedesktop.org/libreoffice/core/commit/?id=3e07bdfce6ef700a94868ccc03268aa005c295b8 Revert "fdo#50183 Use one sheet as default in Calc"
Stephan Bergmann committed a patch related to this issue. It has been pushed to "master": http://cgit.freedesktop.org/libreoffice/core/commit/?id=71056d59de59561ee1d74a3c2d9d66a223422c7e Revert "Revert "fdo#50183 Use one sheet as default in Calc""
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