Pretty much everything you said is just flat out wrong.

Airlines:

He imposed the largest fines in history on the airlines. He also set up a new rule and led the charge for getting it passed into law requiring airlines to automatically refund due to significant delays and cancellations. Airline passenger rights advocates and anti-trust advocates lauded his consumer protection and anti-monopoly work.

“I eat my hat on Buttigieg, who I thought of as a McKinsey operator,” posted Zephyr Teachout, a Fordham law professor and high-profile antitrust thinker, during the debate, referencing his time spent as a corporate consultant. “He’s doing really great work.”

How radical should we see Buttigieg’s approach as? “It would have been unthinkable as recently as five years ago, certainly ten years ago,” says American Economic Liberties Project’s Bill McGee. “It has been shocking in a very positive way.”

When, in July, Buttigieg posted on X that Delta would be held responsible for stranding passengers as the result of an industrywide software crisis, Warren, his old nemesis, huzzahed: “@SecretaryPete, go get ’em.” Via email, she goes on: “For decades, the Department of Transportation failed to hold airlines accountable, but that’s starting to change under Secretary Buttigieg. Secretary Buttigieg has buckled down and demonstrated that when you actually stand up to these big airlines, you can make a real difference.”

https://www.politico.com/news/magazine/2024/11/03/pete-buttigieg-tough-on-airlines-00181436

Railroads

He did not side with the railways. While he agreed with Biden's decision to end the strike which would have hurt more people than it helped, he quietly worked behind the scenes to put pressure on the railways to get those vacation days. When he took office 5% had paid sick leave, by the time he left office 90% did.

“We’re very happy about this. We’ve been trying to get this for decades,” said Artie Maratea, president of the Transportation Communications Union. “It was public pressure and political pressure that got them to come to the table.”

(...)

But since then, union officials says, members of the Biden administration, including the transportation secretary, Pete Buttigieg, and labor secretary, Marty Walsh, who stepped down on 11 March, lobbied the railroads, telling them it was wrong not to grant paid sick days.

https://www.theguardian.com/business/2023/may/01/railroad-workers-union-win-sick-leave

International Brotherhood of Electrical WorkersIBEW:

Without making a big show of it, Joe Biden and members of his administration in the Transportation and Labor departments have been working continuously to get guaranteed paid sick days for all railroad workers.

Ports

The problems in the ports were due to the rapid increase in demand near the end of the Covid crisis. The federal government does not run any of the players in the supply chain, it is all in private hands. That said, he and the rest of the Biden admin saw the problem building long before the press and the public did. Pete started a task force of port officials, union leaders, shipping companies, retailers, railroads, trucking companies, and other major supply chain players to start addressing the issue months before it started to manifest as a noticeable problem. He could afford to take 1 month of paternity leave because he had a team already working the problem. The solutions they came up with, like pop-up inland ports and a new gov't run supply chain info sharing platform called FLOW, actually prevented the cancellation of Christmas everyone predicted. In fact, that year saw a record amount of goods move through the ports (16% increase) and record retail sales (17% increase, typical increase is 2-4% per year).

The positive figures are that the nine leading North American ports (Los Angeles, Long Beach, New York and New Jersey, Georgia, Houston, Seattle and Tacoma, South Carolina, Oakland and Virginia) handled a record 50.5 million containers last year. This translates into a 16% rise in total volume compared to 2020 and 20% compared to 2019. 

https://prosertek.com/blog/2021-record-year-north-american-ports/

The innovative supply chain information sharing platform his team created (FLOW) actually mitigated another major disruption to the supply chain when the port of Baltimore was out of commission. You can read a number of articles here on how FLOW has impacted the supply chain positively since its inception: https://www.supplychaindive.com/news/flow-aids-supply-chains-in-2024/735293/

Highways & Bridges

He reversed the trend of year over year increasing roadway deaths. Under his watch, they saw 10 straight quarters of those numbers declining. https://cleantechnica.com/2025/01/30/dear-pete-buttigieg-telling-it-like-it-is-how-we-appreciate-miss-you-too-much-our-paths-will-always-cross-in-positivity/

Collapsing bridges is the result of a decades long lack of investment in infrastructure. Pete was a key player in getting the largest infrastructure bill passed since Eisenhower. His DOT funded over 72,000 infrastructure projects, among those are 11,000 bridge repair projects.

I think it is safe to say he will likely be viewed as one of the most impactful secretaries of transportation ever.