When necessary then it will be. To do this, you need to do quite a bit of work for 2.2. 2.1 is already a very serious application and for 2.2 it is not very necessary to rush. Now there are more important tasks and bug fixes. In addition, it will be necessary to update the code base for PHP 7.2 and get rid of the hereditary code and compatibility with older versions. Everything needs to be reviewed all the proposals and some specific to implement. Yes, and the editor needs to be updated, but there are tasks and more importantly and there is no need to rush. The code base is already good, which only needs improvement or a census of certain points.
What are new features especially??
It would be important to extend the so-called profile messages.
There are no attachments, activity, emotions, etc.
Who can see the posting? This function is also missing.
The forum is missing e.g. Anonymous Writing, hashtags.
Answer and evaluate questions in the profile.
It seems to me that forums software creators want to create something old of their own,
but this will lead to forums dying out if you don't follow up.
If you don't want it, you can deactivate it!
Is more like it once you start running add ons and styles other than the default. You're not going to 2.2 until everything catches up anyway, so you might as well sit back and enjoy 2.1 before 2.2 and you need to possibly renew a ton of licenses for whatever 2.2 delivers that you can't live without as it may break XF because nothing caught up till (a) month(s) later that's essential to your site.
If you're only running XF then this doesn't apply.