In the end it doesn't matter. They surely could afford a classic realm, they won't make billions with it. It could just be a service to the community but they don't want that obviously.
Thanks for the link... exactly what I thought... it shows
literally nothing about a donation debacle. I don't even now what you want to proof with it?
They got too much players (more than expected), couldn't pay it without donations and asked for it (for a period of time)... the post is a year old and as you clearly can see, the server ran for one more year until Blizzard put an end to it.
It was f2p... a few people donated... everything went well. If more money would have been needed, more peopel would have donated. Period.