Then you seemed to be surprised by the issues, again showing you lacked the experience of a senior. I feel you got good guidance but it feels it was not well received.
The away team experience also felt a bit juniory. Your requests we not priotorized high enough but you didn’t find the tools or means to go around it. Understanding their needs and life in general would be an indication of seniority.
Finally, I think it takes at least a year to see how you are able to cope and progress. It takes time and effort to make any changes in a huge corporation.
In the end, I think that you would not have enjoyed yourself working in that environment so you made the right call. It takes certain character traits to be able to enjoy navigating and gaming such corporate culture.
Source: ex enterpreneur with two decades of experience, atm employed in a >100k employee corporation and loving it.