“The Orthodox Church does not consider spirnkling to be baptism in the strict sense of the meaning of the word baptiso.”
I can understand that, although from a canonical point of view the water must “flow” over the person being baptized, so I have never heard or seen of Catholic baptisms which could be described as “sprinkling”. (We of course also baptise where there is any doubt as to validity in the form or matter of the sacrament.)
Baptiso means to dunk (submerse) repeatedly resulting in a permanent change, as in pickling cucumbers. Contrast that with the word bapto which means to dunk.
The idea is to be "inside" the water and to accomplish this repeatedly, specifically three times (trinitarian formula ), resulting in a permanent change.