One would have to check the timeline to determine whether the second was, in fact, an Mcron innovation. Uwe Ohse's uschedule, which has been around since 2001, also works by individual users having files in their own directories with their own daemons.
* https://ohse.de./uwe/uschedule.html
* http://jdebp.eu./Softwares/uschedule/