Now, you can still open mdb files on Windows, using the Jet Engine and something like ADO, ADO.net or ODBC, but the details of that are a bit too gory for the mild mannered command line junkies here.
Of course, maybe the source of the data was wrong in choosing mdb as the format, and a csv would have sufficed. I don't know, that's not the point here. The point is that mdb is the easiest way to get 'database-like' information that is more complex that just a flat list of records into the hands of 'regular' users, as much as that may dismay those for whose platforms nobody has written software to open them.
For that to work with sqlite databases, one still needs to install a GUI tool first, hope that it associates the right extension with the sqlite file you have, and then get over the database-centric user interface that all of them have.
Look, I'm not saying that mdb is better than sqlite. But I am saying that the notion that the 'openness' of sqlite somehow makes it easier for regular users to open them is a crock.
Or maybe we can talk about if using sqlite databases in simple, 'script-like' applications is easier than doing the same with mdb/Access databases. That is more nuanced and depends on what environment you want to talk from etc. But that goes far beyond the definition of a 'user' as in the use case of the OP (a large student body to whom exam results need to be communicated).