I’ve been to this migration dance as an admin a few times on 3-5,000 member groups in another industry. It’s never easy on anyone at that time.
The undeniable reality is that many of the oldest most established forums in any interest around the world have closed or migrated to become private or closed Facebook groups irrespective of the loss of some functionality in FB groups compared to forums. The biggest loss end users experience is the ability to go to different topic categories but still people see to get over this and still prefer to be on a FB group over forums these days.
Regrettably for the owners of the FB group at this time they are unable to monetize their FB group(s) to the degree they can their forums (phpBB or Xenforo).
Regardless of initial complaints from end user experience or loss of some functionality on Facebook groups compared to their “old forum” they get used to it and besides most of us are already used to participating on Facebook groups. The whole world is mostly used to it now.
Underneath all this are the metrics that the website owners present to advertisers to justify their advertising spends with FA. Private FB groups don’t attract the Google Juice like a website does. This is not a barrier, it’s just a challenge.
IMO FA situation would be best suited to a hybrid solution of using a closed FB group for discussion and then the rest remain on the website. This will still allow revenue from the website and with proper information and promotion of this from the FB site to the FA website will attract even more people to both.
Even as dumbed down as FB groups are I wouldn’t fight the trend too much because when administered correctly these FB groups will result in even more traffic of the right type to the website.
I humbly suggest that all of us should hold short of being too critical and expect some turbulence during the climb.
Thank you to the admins for taking this migration on no matter how it ends up.