feel like a good C# senior dev should know and have noticed a lot of them don't

I love how you're just causally implying that you're a senior dev and most other senior devs aren't on your level because "a lot of them don't" know what you know. we're such pretentious people

Also, weak references??? Expression trees? sounds like you just learned a handful of subjects and want to validate that what you already think you know. this isn't about honest answers, it's about circle jerking with other people who think they're senior devs by saying shit like "you need to know weak references" or you're not a senior dev. such weird gatekeeping shit