It seems (based only on the posts generally written on BP recently) that you are not alone in that observation and sentiment. Of course, there are also the passive lurkers and we do not know their opinion - except that at least one regular poster has observed a significant decline in readership levels, too.
But I think this issue is not solely due to the change in site platform nor even just to the attitude of the site owners,
I see (at least) three major changes going on and they are strongly interrelated in their impact:
1) the site itself which is very impersonal as well as all the other factors which have been mentioned about it and the owners' policies,
2) the quality and quantity of Newbie issues raised. It really gives the impression that hardly any Newbies are prepared to actually study anything and just want everything handed to them prepacked and with a profit guarantee. The general level of questions raised is so naive that I cannot believe these people have tried to understand anything beforehand. Also, I suspect that general interest is moving rapidly away from manual trading of standard forex to the cryptocurrencies and automated systems. Perhaps that is understandable and inevitable, given the more widely recognised and accepted poor success rate in forex and its learning curve duration expectations -i.e. it is not instant and fails anyway!
3) the only reason any genuinely experienced and consistently profitable trader would frequent this site is to help genuine and conscientious Newbies in their development and progress. But if one starts to recognise a laziness and reluctance to study amongst Newbies then one no longer feels any inclination to help, knowing that the person concerned will inevitably fail and usually disappears off BP after only a few posts anyway? So these traders gradually lose interest and move on. It also seems to generate a level of cynicism, sarcasm, and aggressiveness in responses from such experienced traders that rarely used to be here. That is also relatively understandable, albeit a regrettable weakness amongst such traders.
I have recently "muted" all the soft-sale and commentary threads and all those long-term junk type threads, and, to be honest, what is left is so little and so uninspiring that I rarely respond to anything anymore (which may well be an advantage for the OPs anyway, but that is another issue!!).
And on the other hand, any threads that seem to be actually trading-oriented do not attract much input at all!
It is not my intention to get involved in this thread any more than to mention these personal observations and I will now be muting this one too.......