Any tips for writing for brass section?

I was wondering if anyone could explain why when writing for a brass section using a DAW, that people have a tendency to start the notes before the strong beat? I understand the idea of wanting to make it sound with more realistic, but what if you want to be able to score the song later? The syncopation theory helps, but I guess the only logical thing that I can think of is if they want to add some automation clips to its velocity, volume, or expression? Can someone elaborate on this theory?

Can you give a specific example (like maybe a music clip) of the problem you're describing? My obtuse brain isn't following.

Which could mean that I'll be of zero help here.

https://youtu.be/f-PnVWkmBAk       Around 1:35 you could see some examples of how the notes start before a strong beat. I'm picturing that its because brass and woodwinds take a little bit to spool up, unlike the strings. Between that, automation clips and to get it sounding more human like. The issue I see is what if I want to write something that I want scored later?

I hadn't noticed it as a tendency. The link you give is about creating an amorphous wall of sound. I don't think that necessarily relates to brass writing in an orchestral score. Slight off-beat notes on and off may help to humanise a piece as you observe. Sorry I can't help.