After creating a new project with
This is an intentional change in one of the latest versions.
The distinction is pretty arbitrary for front-end apps that produce static bundles. Technically you don't need any of these dependencies on the server, not even the runtime ones. So by that logic even
react might be seen as a development dependency.
We used to try to separate them but as explained above, it isn't really consistent in the first place. There's no technical reason why this distinction is useful for apps that have no Node runtime. In addition, it used to cause problems for some Heroku deployments that didn't install development dependencies (and thus weren't able to build the project on the server).
In the end we went with just putting everything into dependencies. If you disagree you can always rearrange
package.json as you deem reasonable.