Have you considered using patterns that help dealing with that?

like Railway Oriented Programming

https://www.youtube.com/watch?v=45yk2nuRjj8

I believe that almost every thing should return Result<T>, because almost everything can fail and compiler should scream when you do not handle those fail pathes.

That makes me believe that C#'s "FirstOrDefault" for value types sucks, because you're never sure whether the "Default" comes due to lack of value or because the found value is actually the same as default

e.g

var list = new List<int> {1,2,3};

var found = list.FirstOrDefault(x => x < 1);

found = 0 (default)

meanwhile 0 may be valid value! so we aren't sure whether it is error or an actual value

and we have to perform e.g casts to `int?` or stuff to detect that.

using Result<T> gives very precise information