To me, it's a failure to use common sense that these passengers would be denied boarding.

Boarding nine people would have taken about a minute to scan the boarding passes and, with flight attendant assistance, about 2-3 minutes to get them seated.

Not boarding nine people means that an agent has to spend 5 minutes with each party rebooking them, not to mention the inconvenience to the customer.

The airline sold the connection as a legal connection, so the fact that it was only 35 minutes doesn't really mean much to me.

My only recent anecdote about close connections and the way they're handled came last week flying LAX-ATL. Several people were connecting to TLV. LAX-ATL was a bit late because of the ATL weather and runway situation. The original gate assignment was T2 for the LAX-ATL arrival, meaning those connecting to TLV (and their bags) would have to make it to E concourse. There was still about 30 minutes to connect available, despite being late. The 764 landed and headed toward T concourse to the assigned arrival gate, but somewhere between C and B terminals, while on the taxiway, the pilot does a U Turn, then comes on the PA to tell everyone that in order to make sure all the TLV passengers make their connection, the arrival gate has been changed to E concourse. And at the gate, there were Delta reps looking for TLV connecting passengers in order to expedite their transit to the departure gate.