At the risk of trending off-topic, it's not access to the data that's the biggest risk. It's possible, and not very hard, to read native Esri file-gdb and to some extent SDE with QGIS and friends in place (as a matter of fact using the open source file-gdb driver you can read more data types than the official Esri file-gdb driver can). You don't get everything, relationship classes come to mind, but the core there.
Similarly I can still read all the data for any of our thousands of archived ArcView 3 projects with any current GIS program today, regardless of whether they are free or very expensive. However without running the program we can't get to the projects, and that's important.
Projects are where the business logic is, the queries stacked on queries. It's where the cartography is.It's where the value added thought goes. In ArcGIS Desktop it's in the .mxd's custom chained tools and scripts and models. ArcGIS Pro has it's own version of the same. In any given working-on-gis day I'll spend a quarter to a third of time on raw data creation and manipulation, the rest of the time is on things that aren't captured in shapefiles or database tables.
In short, I'm not (very) concerned about losing access to the data. Data value is portable, more or less, with a relatively low investment and time and energy compared to exporting Project value.