There are fewer hacks nowadays, and they’re usually less ambitious, but I would argue it’s for reasons other than hostility from the Institute.
That hack in particular took multiple months of preparation and was took down by the institute in less than 1 hour; before anyone could really see it. Also the amount of security and possible consequences has increased drastically in the last 2 years; continuing the trend of the last 6 years.
I have some further opinions about what you allude to at the end of your comment, but that should probably be taken offline.
http://hacks.mit.edu/Hacks/by_year/1999/r2d2/
Several Lobby 7 hacks were also left up for a while (though admittedly less obvious and dangerous perhaps than Great Dome hacks).
I know people who were at MIT then. It was, by all accounts, a vastly different place.
They did the annual sodium drop pretty soon after 9/11 and were somehow surprised when the response was different.
For smart people, they could be really, really dumb.
I don't know how structurally sound the surface was there but if I had a season-ending injury because I stepped on a balloon or because my leg fell through the grass then I'd be pretty upset about it.
Let me just say if someone did the dome hack at my alma mater 1) nobody would get the reference 2) the perpetrators would be expelled or criminally charged.