It is. It could be construed as a form of constitutional brutalism: in theory the president is free to name whomever he chooses, however he is expected to choose someone from the parliamentary majority.
But this is the first time in the history of the current constitution that the parliamentary majority isn't an absolute majority or cannot form an absolute majority coalition. The consequence is that they can't systematically no-confidence-vote out any head of government they don't approve of, and basically enforce this expectation directly.
So Macron can just name someone from his minority (3rd biggest group even) and wait for the parliament to (more or less slowly) disagree enough with it that they'll agree to no-confidence-vote it out (usually when the government proposes a budget). Then, every time a prime minister is ousted, he can pretend he's not violating the constitution -- in spirit if not in letter -- when he starts again. He can frame it as defending the republic against "extremes" even though the relative parliamentary majority he's "defending against" is just a loose leftist alliance between parties that span from barely liberal to a bit more angry, but not extreme even by the state council's own definition. The second biggest group, however, is actually the far-right authoritarian racist party founded by literal ex-SS that's going to win a presidential election at some point if he keeps trying to out-authoritarian them.
"Less than a month" isn't conveying the absurdity of the situation. He spent "less than a month" in discussions to agree on a government (which was actually very long). He resigned - taking said government with him - less than fifteen hours after settling on one.
Then Macron rehired him for 3 days, he said he'd leave then, and Macron said "alright then 5 days". We're living in a Month Python skit.