As a matter of fact, I hear it from the same people as well, but not always. Its merits would remain regardless of who says it.

The 1984 indult Quattuor Abhinc Annos was replaced by the 1988 indult Ecclesia Dei, and more recently by the 2007 motu proprio Summorum Pontificum. The latter is where Pope Benedict XVI called for a co-existence of both forms of the Roman Mass, to enable a "mutual enrichment" of one by the other. In this case, it would depend on the "features" to which you refer. In any case, it is a far cry from the notion of "mixing rites" that was prevalent in the 1984 indult.