How do I insert copyright info into nuget's SPDX license expressions? - nuget

Question

As detailed here, nuget has deprecated the licenseUrl tag in favor of the license tag, which can either specify the path to a license file or a Software Packaging Data Exchange (SPDX) expression; for example, you can specify that your package is distributed with an MIT license as follows:
<license type="expression">MIT</license>
This is very nice, but after running nuget pack (with nuget 5.4) and examining the resulting package in either Visual Studio 2019 or NuGet Package Explorer, for the license I am linked to https://licenses.nuget.org/MIT and see this:
SPDX identifier
MIT
License text
MIT License
Copyright (c) _____
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
So the copyright isn't filled in. Is there an SPDX expression to fill in the copyright? Or is the nuget client just supposed to be smart and fill that in from the copyright field of the nuget package itself?