The WSJ has come out with a piece attacking Buttigieg's war service.
https://www.wsj.com/articles/buttigiegs-war-and-the-shortest-way-home-11578355312
The gist of the article is that veterans of the service have low opinions of the type of service Buttigieg performed. He direct commissioned into an officer role in the reserves and did a few months of office and staffer work overseas, then returned and retired from the reserves.
The article points out that direct commissioning is often seen as a back door to military service for the well connected. Direct commissions do not have to attend ROTC or OTC training like a normal officer candidate. They don't even have to attend basic training and be evaluated based on all the normal things a soldier or officer would be evaluated for, such as physical fitness, combat proficiency, and leadership ability. Instead, they receive a direct commission and enter immediately into military service.
The article points out Hunter Biden also received such a direct commission, which he then lost when he pissed hot for cocaine.
The article points out the dramatic way in which Buttigieg describes the risks he faced. He largely performed office work and occasionally had to drive a car outside the base as his role as a support staffer.
A cynical person might suspect that this was a calculated, low effort way for an aspiring politician to beef up their resume without actually putting in the hard work and commitment of being a soldier.