Yes, there are valid concerns regarding densified propellants. Can those be mitigated, to a degree. SpaceX has now multiple years of handling densified propellants... However, just stating that they've done it a certain way because, well they've done it a certain way.
Let's think this out.
Scenario 1. Vehicle is dry. Astronauts and Techs ride up the elevator and get Astronauts situated the vehicle. Technicians then leave the pad. Abort system is verified and enabled. Propellant loading begins.
Scenario 2. Vehicle is loaded and oxidizer boil off is occuring, which means the Astronauts and support staff will be riding up an elevator next to a loaded rocket, plus the strong back will have be supplementing the vehicle so it's going to have a substantial amount of cryogenically cooled oxygen in it as well. Now, once the crew is loaded, the technicians need to safely get down the elevator and away while boil off and supplemental loading is occuring
Which of these scenarios seem more likely to be a recipe for disaster?
I called this a hit piece because this is looks from the outside like SpaceX is being forced to jump over much higher hurdles than ULA.