They're providing beautifully made ebooks for free...

The only thing they are is truly, truly wonderful.

But why not be true to the original author's text? What's the need to modify it?

Not parent, but while I can appreciate your viewpoint, I would like to point out that many many many books have abridged, reworded, simplified, or disambiguated versions for different audiences.

The Bible is I daresay the most famous of these. Translations aside, even the English versions have had significant alterations done to wording, spelling, and meaning depending on the version.

There's also the Great Illustrated Classics imprint for certain classic novels like H.G. Wells's The Invisible Man. (I read that one like 10 times as a kid and it's what got me into sci-fi as a whole I'd argue. Haha.)

Whether these alternate versions are good or bad is obviously up for debate and depends on the person, but I'm just saying that what SE does is hardly new in the publishing world.

SE is an amazing and wonderful resource