You've been told by several members though that they have reduced their activity, which in turn leads to less business.
A practical example as to why personally I am uncomfortable browsing with this feature. What if prior to this feature the way I use the forum is just to keep up to date with the market and view all of the for sale posts. Previously you'd be able to just click through the list and get on with your day. Now with this feature you have the risk of two things, one the owner of the domain directly messaging you and two being spam further down the line of someone with a similar domain trying to sell a different domain.
So now I have personally adjusted how I browse these forums, I am not interacting with these posts due to the above scenario, as someone who has spent comfortably over £10k on domains from this forum it's lost a potential buyer, based on the replies above it's lost numerous. A good feature should increase engagement and visibility which based on public opinion this has not done.
It doesn't show that it has quality users though, that's done by people posting. If anything it's leading to potential confusion, you've got the typical "views" that show as of right now 494 views. However there are only 36 members who have viewed the thread.