Some stats on the likely effect of this change:

Number of new posts during the two-week period between August 18-31 (before this change): 131219
Number of new posts during the two-week period between September 22 - October 5: 142907
Increase of 11688 posts or +9% (helped in part by Yobit I would assume).

However the number of new posts on the 4 affected boards (for the same time periods) is...

Before: 58406
After: 46781
Decrease of 11625 posts or -20%.