That functionality was broken a long time ago, it occured due to some incompatibilities between the forum software/upgrades to the rest of the site.
I assume you never read the New Member topic?
https://forum.freecapitalists.org/t/new-member-read-this/18258
What I personally do is every time I click on a reply, in the address bar you will see “&Quote=False”, I just change it to “&Quote=True”.