Obviously you have missed the point. The Byzantine Liturgy is unreformed, it is ancient and time-honoured. The ritual has hardly altered over centuries.
The Roman Rite was in much the same position until 1970 when an ancient and time-honoured Rite was replaced by an ersatz, committee-fabricated ritual in order to appease Protestantism.
This is not about the language of the liturgy at all, it is about the very liturgy itself. The Patriarch of Moscow has heavily criticised the liturgical reforms subsequent to V2.
The major criticism of the Novus Ordo is not the language although the English leaves much to be desired, it is the deliberate downplaying of the sacrificial nature of the Mass.
Orthodox Churches ought to be wary of union with Rome if it reserves the right to Protestantise their liturgy by papal or conciliar decree.