https://www.gnu.org/software/mit-scheme/release.html
Stable release 9.0
In the past my (Chris Hanson's) policy for a stable release was that the documentation had to be updated for the release before it went out. In practice, this has meant that there have been no stable releases in recent years. As of this release, we will no longer consider updated documentation a prerequisite for a stable release.
No chance of competing with python like this.