I think the main problem with Bun is that they are trying to move very quickly.
Tigebeetle devs spend 90% time working on stability, safety, tests and so on. They don't need new features, they need reliable software. Their database is pretty simple in terms of features and their goal was always stability and speed. Bun devs spend the majority of the time adding new features.
Maybe they should put more consideration towards quality if they have a ton of memory issues.