there was virtually no security at the hotel?
Were we looking at the same event?
The hallways were full of uniformed Secret Service agents and there were several plain clothes/undercover agents in many of the initial images.
There were also many uniformed local police (one took a round in their bodyarmor).
There were magnetometers for screening guests.
There was a fully kitted counter assault squad standing by close enough to be on stage in about 10 seconds.
The airspace was restricted and there were agents on the roof with counter drone weapons.
There were multiple layers of security.
All he managed to do was to sprint through an initial screening point and right into a hallway full of federal agents and local police where he was subdued.