The issue of whether the verses that are missing from the new Bible versions - and from the Westcott-Hort Greek text - were added to the Textus Receptus, or the Vaticanus and Sinaiticus Greek texts left them out depends on some scholarship. The Westcott-Hort Greek text is based largely upon the Vaticanus and Sinaiticus texts which are associated with Alexandria, Egypt and the Christian and gnostic theology going on there in that period.
The Greek manuscript basis for the Textus Receptus is said by the scholars to be more recent than the Vaticanus and Sinaiticus used by Westcott and Hort for their 1881 Greek text. This does not necessarily mean the Byzantine Greek text itself is more recent than the Vaticanus and Sinaiticus.
The "scholarship" of Westcott and Hort was mostly a set of assumptions, and among those assumptions was the idea that the shorter verse wordings of the Vaticanus and Sinaiticus indicated these texts were closer to the originals. Another assumption was that the scribes who copied the Byzantine Greek texts over the centuries made mistakes and Westcott and Hort go into details on the type of errors these scribes might have made. Yet, scholars and other Christians note that the various manuscripts of the Byzantine type show more agreement with one another than do the
Vaticanus and Sinaiticus. This suggests the Byzantine scribes did not make the errors in copying that Westcott and Hort claim they might have made.
See: Translations and the Greek Text
There are papyri Greek New Testament manuscript fragments earlier than the fourth-century Vaticanus
and Sinaiticus manuscripts, and most of these have been discovered after
Westcott and Hort's time.
See: http://www.uv.es/~fores/programa/majorityvscritical.html
Many Papyri fragments of the New Testament contain Byzantine readings,
that is, the verse wordings are more similar to the Byzantine Greek
text than to the Alexandarian text, used by Westcott and Hort for
their 1881 Greek text, and from which almost all recent New testrament
versions were translated.
"Harry Sturz discusses these "distinctively Byzantine" readings in his
book, The Byzantine Text-Type and New Testament Textual Criticism."
"The most important of these discoveries was several Egyptian papyri.
Sturz lists "150 distinctively Byzantine readings" found in these
papyri. Included in his list are papyri numbers 13, 45, 46, 47, 49,
59, 66, 72, 74, and 75 (pp.61, 145-159)."
"Sturz brings up another very important point about these papyri,
"They attest the early existence of readings in the Eastern part of
the Roman empire in which the Byzantine and the properly (i.e.
geographically) Western witnesses agree and at the same time are
opposed by the Alexandrian" (p.70). "
What Sturz is saying is that many early Papyri Greek texts agree with
the verse wordings of the Byzantine or Textus Receptus type Greek text
more than with the Alexandrian or Westcott-Hort type Greek text.
"Sturz concludes, "In view of the above, it is concluded that the
papyri supply valid evidence that distinctively Byzantine readings
were not created in the fourth century but were already in existence
before the end of the second century and that, because of this,
Byzantine readings merit serious consideration" (p.69)."
"Aland says all but one of the these early papyri, "... are from Egypt
where the hot, dry sands preserved the papyri through the centuries."
Meanwhile, in Asia Minor and Greece (eastern areas), "... the climate
in these regions has been unfavorable to the preservation of any
papyri from the early period" (pp.59,67)."
The writer of this site then says "So it is not surprising many early
papyri have been found which reflect the Alexandrian text since this
text existed in Egypt. But even some of these Egyptian papyri, as
mentioned above, contain Byzantine and even Western readings."
Westcott and Hort claimed that a criteria for selecting a Greek text
was its shortness, that is, shorter verse wordings, they claimed,
meant the text was older and therefore more 'authentic."
"The papyri discovered since the 1890's are the Oxyrhynchus papyri in
1896ff., Chester Beatty papyri in 1930-31, and Bodmer papyri in
1956ff. They represent a 600 percent increase,[86] and 31 are pre-300
a.d.[87] The more important ones (P45, P46, P47, P66, P72, and
P75--these are equivalent to one-third B text and represent every New
Testament book except 1 and 2 Timothy)[88] represent a several
thousand percent increase as far as their importance."
"The finding of many early papyri New Testament texts in the twentieth
century has shown that the Byzantine, the text behind the Textus
Receptus, has very early support."
"Zuntz also found P46 to be a witness to the existence of Byzantine
readings in the second century."
That is, in the second century A.D. there were Byzantine type verse
wordings in existence as shown by a few Papyri from that period. This
does not necessarily mean that the Byzantine wordings, probably
originating in Antioch, Syria, did not exist in ever earlier times.
"Zuntz concludes his study of the epistle's text by stating that after
around 150 b.c. the oldest papyri "rather suddenly . . . give a text
which substantially agrees with that of the extant Byzantine
manuscripts."[95] Thus Zuntz acknowledges that the Byzantine readings
"are far older than the manuscripts which attest them."
The writer of this site then points out that "When one considers that
there are only a minority of the various text-types that vary, they
all must have a common ancestor. Thus those who reject the Byzantine
text do not have an easy task to prove their position. Their position
is much more difficult than Hort thought."
"Early Church Fathers' quotations do not support Westcott-Hort's text
either. This is even recognized by those who do not support the TR.
(Textus Receptus) Price, who does not support the TR, when writing
about recent progress in textual criticism, said, "The Westcott-Hort
'Neutral' text was found to be practically without support in the
earliest fathers."