I totally agree with OP. The 1000 chars for a post in english is absurd.

I post on forums not too often but when I do I try to make a decent write ups where people do exactly understand what I meant to say to prevent silly questions and trolling.
I often try to write my reasonings for people to understand me even better. This is a forum where we do discuss things and not a twitter where you don't want to read through walls of text cause you have to read them all.

IMO limiting people in this way only hurts community. And it will definitely not beneficial for a forum storage database cause people WILL write their thoughts but probably will split them into several posts.

BTW there was not a single post from me that I could fit into 1000 chars. Posts like "ok" of other 1-word posts are actually useless in terms of discussion.