What I Wanted to Do
Check the license for React v15.5.2
What Happened Instead
The website appears to have the wrong license for this older version of React
https://www.npmjs.com/package/react/v/15.5.2 shows that the license is MIT (on the panel on the right, right next to the version number).
However, for that version of React the license appears to actually be BSD: https://github.com/facebook/react/blob/v15.5.2/LICENSE.
The license seems to be correct when accessed via the npmjs api:
curl https://registry.npmjs.org/react/ | jq '.versions."15.5.2".license'
It is worth noting that react now uses the MIT license. Could it be that the website simply shows the latest license rather than the license that was used for that particular version? Github seems to make this error as well. But the npmjs API does not.