Yes. This name HE WHO IS is most properly applied to God because of three reasons:
(1) it signifies simply existence itself (since the existence of God is His essence itself, which can be said of no other)
(2) it is most universal (it determines no mode of being, but is indeterminate to all; and therefore it denominates the "infinite ocean of substance": pelagus substantiae infinitum et indeterminatum)
(3) its consignification (since it signifies present existence, and this above all properly applies to God, whose existence knows not past or future)
Note RO2: This name HE WHO IS is the name of God more properly than this name "God," as regards its source, namely, existence; and as regards the mode of signification and consignification, as said above.
But as regards the object intended by the name, this name "God" is more proper, as it is imposed to signify the divine nature.
And still more proper is the Tetragrammaton, imposed to signify the substance of God itself, incommunicable and, if one may so speak, singular.