Thanks for the reply! These are good questions.

In real life, endowments and real-estate donations are often given with constraints on how the gift can be used by the recipient, so if large amounts of funds for the endowment were to be donated by someone on the Steem blockchain, it might be prudent to try to stipulate terms on the sorts of voting and content-creation behavior that are permitted or prohibited.

As to whether the blockchain community would be welcoming, I guess it depends on a variety of factors, but the endowment would need to navigate the same landscape as anyone else on the blockchain. As long as the votes and posts are geared towards promoting useful content, I'd hope that they'd be supported, but this is an important factor for consideration, because it clearly adds some uncertainty to the idea. (This is one of the concerns I have had with downvotes in general. It's not really limited to the endowment idea. For example, what if a major music label decided to launch a downvote campaign against all people who post competing music-videos...)

It's also interesting to think of what might happen if someone did start voting to counter the rewards of a school with 10 or 20 thousand active students or more (and their families and alumni). Might that academic community respond by buying more Steem and launching a "bidding war"?

I have to say that I don't know, but those are interesting and important questions for anyone who might consider pursuing a strategy like this.