I'm not even sure what a "Tridentinist" is when it's at home. I'm a Catholic who prefers the traditional form of the Roman Liturgy. I have never been to Tridentinum (Trent to you and me) and have very little interest in going. There is also this worrying trend of juventophilia, an obsession with pleasing or attracting the young. If you have a very popular, youth based ecclesial movement, it doesn't necessarily mean very much. It could be like the "Gospel Mass" (i.e. Mass with Black American style choral music) that is celebrated in a certain Dublin Church; it attracts the crowds but has had the Gospel liturgically proclaimed by a lay woman! Yes, they are going to Mass but are they being edified, built up in their practice of the Faith?
In any case, it is a mistake to see liturgically traditional and non-traditional Catholics as mutually exclusive categories. For example, Youth 2000 is a vibrant organisation which is very successful in youth evangelisation here in Ireland. I have trad friends who are members of Y2K prayer groups; many Y2K members with a more Charismatic background are finding the traditional liturgy more and more attractive. Y2K also has a contemplative side with a great focus on Eucharistic adoration. As a card-carrying trad, I find this to be a very good thing. In the end, however, people will go where they can pray best; this is one of the greatest gifts that the Holy Father has given in Summorum Pontificum. We no longer have to be card-carrying "Tridentinists" or anything else to derive full benefit from Holy Church's liturgical patrimony. Benedict XV of happy memory had the right idea:
It is, moreover, Our will that Catholics should abstain from certain appellations which have recently been brought into use to distinguish one group of Catholics from another. They are to be avoided not only as "profane novelties of words" out of harmony with both truth and justice, but also because they give rise to great trouble and confusion among Catholics. Such is the nature of Catholicism that it does not admit of more or less, but must be held as a whole or as a whole rejected: "This is the Catholic faith, which unless a man believe faithfully and firmly; he cannot be saved" (Athanasian Creed). There is no need of adding any qualifying terms to the profession of Catholicism: it is quite enough for each one to proclaim "Christian is my name and Catholic my surname," only let him endeavour to be in reality what he calls himself.