It is true. Every translation weakens the English understanding of the Hebrew/Greek text in some areas and strengthens it in other areas.
Case in point. My English version of choice for my personal reading and study is the New KJV. (This is largely due to my "Byzantine Priority" textual position.)
1 Corinthians 1:18 in the NKJV reads "For the message of the cross is foolishness to those who are perishing, but to us who
are being saved it is the power of God."
However, the same verse in the old KJV reads "For the preaching of the cross is to them that perish foolishness; but unto us which
are saved it is the power of God."
The NKJV seems to be saying that salvation is a process but we know, from other passages dealing with salvation, that salvation is punctiliar in nature.
So, what is the problem? The problem is not with the Greek but with English.
In Greek the word σωζομενοις is a present, passive, participle. The first thing I learned in seminary in "bonehead Greek 101" class over 40 years ago was the non-temporal nature of Greek participles.
However, in English we indicate the participle by using the words "is being" or "are being." But that gives a false impression when read by an early 21st century English speaker that salvation is a process.
The NKJV employees the technically accurate way to translate the Greek participle, but due to the inexplicable vagaries of modern English, it gives a false impression.
The better (in my opinion) way to translate the word would be to treat it as a "state of being" verb. (And, to some extent the NKJV does that if you "read between the lines.") "(B)ut to us who are
(in the state of) being saved . . ." etc.
The old KJV and the ASV (which I consider to be one of the most accurate English versions) both read "(B)ut unto us which are saved" treating it as a simple past tense which is technically inaccurate but does a better job of bringing the intent of the Greek into English.
So, yes, every version has its strong points and its weak points. That is unavoidable when translating from one language to another. It is part of the curse of sin (Babel). It is why, again in my opinion, that every pastor should have a good working knowledge of both Hebrew and Greek (and I don't mean listening to a tape from a diploma mill) if he is going to take the preaching and teaching of the word of God seriously.
However, on the other side of the coin, that exercise in the original languages of scripture rightly belongs in the study and not behind the pulpit or lectern. By constantly remarking that "the (English version of choice) is wrong here and should read" is contrary to good sense. All it does is destroy the confidence of the hearer in their English bibles. Statements should be in the sense of augmentation never contradiction. "What the phrase here means is something like "in the state of being saved." Never "the translators got it wrong here!" Never say from the pulpit or lectern that which will compromise the hearer's confidence in the word of God!