He'd be Pete but better known and with more party establishment backing, which is to say he'd be the nominee. And then he'd win.
I think you're seriously overestimate the electoral appeal of Macron/Buttigieg-style candidates.
Macron becoming President should be attributed to an incredible series of luck rather than strength. With the collapse of PS (due to Hollande's unpopularity, internal division and Mélenchon undermining it from the far left), and division within the mainstream right, he lucked out to emerge first among a divided field and, once confronted with Marine in the runoff, he was basically guaranteed to win by default.
Now, as of Buttigieg, even if he was better known, had more establishment backing and experience, that doesn't change much. The voters don't really care about "experience", and as of the establishment backing, it might've helped in the Democratic primary, but was proved essentially irrelevant in the general election.
In general, Macron/Buttigieg-type candidates come across as arrogant and out-of-touch latte liberals, which you may find appealing, but this isn't something voters in general share with you. While someone like Biden has a common touch, and Sanders could capitalize on the "anti-establishment" hype, making them strong contenders in GE, someone like Macron of Buttigieg would be quite vulnerable against Trump.
