Judging by the cluster labeled as Euryarchaeote{0+3} in Figure 2 Methanomassiliicoccus was not reclassified into Thermoplasmataceae but to an yet un-specified class.
However, the reclassification of Methanomassiliicoccus into Thermoplasmataceae needs more explanation. To be objective, authors should address the following question, why in the same family and not in another new family?