Sure, we are good at reading people. But so are EIE, IEE, and ESI. We all have different methods of doing so.
In general my EIE mom and I have the exact same insights and conclusions about people. We will get into these in-depth conversations with the same observations so I think a lot of reading people's moods is Fe because she has little Si and I have little Ni.
ESE will use stored information about a person and pull it from their Si to compare past and present behaviors to see if they are consistent as well but its mostly Fe we use. We also have decent Ne that helps us figure out someone else's motivations. IEE use their Ne, Fi and unconscious background 4d Fe to read people.
To contrast SLI, ILI, don't value reading into people's states and emotions. They might struggle with it as well. They are fe polr.
There is some talk that ESEs can't go deep or lack a rich internal world or understanding of what is around them due to Ni polr. I don't think that is quite true. I feel very rich and powerful emotions and can sense them in others. But I'm also an E4.
Perhaps what you are referring to is that ESEs like public displays of affection and verbal affirmations much unlike the ESI and EII who prefer Fi and don't require external shows of affection to prove a bond. Yes, we like declarations that people like us! And that is why you probably won't see us with an ILI or SLI as we need some external proof of their affection and often. LSI and LII can compliment and give PDA with their 1D Fe. It is weak but around us they feel encouraged to use it.
It doesn't mean we aren't deep or don't see what is not there. We just need someone to speak to us in our own language like every type. Don't go speaking Se to an EII you will piss them off. Don't speak Ni or Se to us all the time!
It is the same with a LIE. Talk to them in Fe enough and they will get annoyed. You speak to each type in their native language

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ESE like external ethics. It is our main language. Call it shallow or lacking or whatever but that is what it is and how we see the world.
Reading between the lines is mainly ILE, IEE, EII. ESE and EIE do it too. I know I do.