It looks like the Xbox Series S is facing serious memory allocation issues in Borderlands 3, at least according to Reddit user u/jokekiller94 — who posted a screenshot of the game crashing on their Series S console with an "out of memory" error on the screen.
The issue isn't limited to the original poster — Reddit user u/bacon_sammer responded in the thread, saying they have the same issue with Borderlands 3 crashing frequently on their Xbox Series S. They said the game runs fine on the Xbox Series X, however, so the it seems to be a Series S issue.
Sadly, this type of memory allocation issue is not uncommon for Microsoft's little console. According to reports from Digital Foundry and The Verge, the Series S' small memory capacity is a headache for developers to optimize around. It is the single biggest contributing factor to the console's lower graphical settings and lack of ray-tracing effects on Series S ports, and it bottlenecks the console's already weak 4 Teraflop (PS4 Pro level) GPU.
Apparently, complaints among developers regarding the Series S' memory became so extreme that Microsoft released a dev kit in June 2022 that gave developers more manipulation over the Series S' memory system.