I hadn't checked the timing, and thought about saying so.
Bareilles had done her first stint in Waitress the year before, while Groban was doing Great Comet. And, Tony nomination aside, I don't know if anybody would argue that Groban is talented actor based on his single stage credit. For on-stage experience, they surely had the slightest resumes.
And yes, Rosie, but even she had experience (besides Grease) getting up in front of a live audience day after day and playing a character.
None of the three are trained actors, though, so maybe that's "untutored enthusiasm." Or maybe what he meant is "not Broadway enough." which is no clearer and a dangerous path to tread.