Since the bumping score is calculated differently is the reply considered a "bump" there (if you don't have bumping power for example) and it doesn't bump the thread?
For the bump score, it doesn't matter how many times someone posts:
If you haven't posted in a topic in the last 7 days, posting in it adds 1% of your base bump power to the topic's bump score. Deleted posts count against the 7-day limit, but not the topic's bump score.
In the Altcoin section you have a situation like, an announcement and then reply to a user in a separate post in the same day
Even though technically it's against the rules, it might not be that bad to respond to another user in a separate post after a large generic announcement. Without that, the response might be overlooked by scrolling past the announcement.