Forbes tried something similar a while ago, by preventing ad blocker users to access their articles. How did that work for them?
But if they're sticking with that behavior, maybe it's not so bad? I also saw that their physical magazine readership is up (while other competing magazines are down or flat).
[0] https://thestack.com/world/2016/04/21/sites-that-block-adblo...
Taking bets on them being out of business or sold at a greatly diminished value in 3 years or less.