Whether or not someone can clear it using DF is not the point but even so second coil I believe can be done with DF just like EX's and T5 can be. I have gone into great detail about the fallacies surrounding PF groups of late and the requirements they put on the listings so I won't do it again however this assumption that DF groups cannot clear content is also something that needs to be stopped as it is not true. It is harder sure because your opening up to a lot more people to join your group so finding people who can do it is like drop in pond from PF to drop in a lake in DF...but to say a DF group cannot clear content like 2nd coil is wrong. The same thing was once said about EX trials, ST/CT and the original coils 1-5 when they got added and opened up to DF but all of these often get cleared using DF and not just PF.
Watching a video on it multiple times or reading guides too multiple times is enough for most people to become skilled enough to clear it and additional information like deciding who's going to kite or handle x, y or z is easily decided at the start of the run. Personally I would use the DF version to train and to teach others, help others plus while doing it you will run it with vastly more people than a PF group will ever have, people who you can gauge their ability to progress and whether or not get along with them. Not forgetting you will also have people who were no longer part of statics who might also be using DF despite having cleared the content prior. People you come across during DF runs could then become part of a linkshell or friendslist which can go to and make statics or help with PF''s too. There is no major downside to opening up 2nd coil to DF, it is just an optional and additional way for people to run content on top of PF and statics.
So the main point is people would like to use it as another option of which to enter and take part in content, whether to just learn or to complete content and there is no reason why it should remain locked with a pre-made requirement anymore now that is old content. Those who want to continue using PF's or Statics would not be stopped from doing so just because another method opened up to those who do not want to use PF or have enough time or friends to make a static. Noone should be against removing that requirement at this stage, noone has a good enough reason not to allow for DF to be used to gather and form parties for 2nd coil anymore now that final coil is out because it does not stop anyone using the previous methods for doing it if that is their preference.