>>88517689Japanese really fucks with grammar a lot and they omit it very often.
Grammarwise it feels like Japanese is not concise at all, valid Japanese is very often grammatically incorrect and they don't care as long as it is understood. That is why just learning it by Input is the correct way, but any native speaker of any language mostly learns grammar by input and trying to replicate it.
Again, は and が are very different, it's just in very simple cases that は carries the same meaning as が which is almost always when you would see it as am/is/are ("I am", "You are").
The specific is that が in general is more explicit and can be understood demanding when an action is mutually exclusive like who would do something (I will be the one who pays for it). In these cases you can omit は anyway.
I always see for what it is which is the Topic Marker and just connects two sentences where the meaning of sentence B applies to a topic specified in sentence A. It's nothing that can directly be translated just try to see it as something that has a function or purpose. As a Software Engineer I struggle less with that as you deal with abstract concepts often.
