Why is this verse on the Trinity, 1 John 5:7, missing in many modern bible translations?

Various scholarly commentaries on this verse are in agreement on the following points:

REASONS:

(1) They are not found in a single Greek manuscript earlier than the fourteenth century.

(2) Not one of the Greek or Latin Fathers who conducted the resolution of the controversies about the doctrine of the Trinity in the third, fourth, and first half of the fifth centuries ever quoted the words.

(3) The words occur first towards the end of the fifth century in Latin, and are found in no other language until the fourteenth century.

(4) It is not found in all the oldest versions. The oldest manuscripts of the Vulgate does not has it.

See the picture of the oldest Bible manuscript bellow (from Codex Sinaiticus). It lacks the verses on the "trinity".

Read also, by clicking the link bellow:
37 Bibles that Removed Trinity verse,1st John 5:7
https://www.nairaland.com/6986742/37-bibles-removed-trinity-verse#110227898

For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one.
1 John 5:7 KJV

It's still there but there's isn't anything like trinity.... At the bold letters, it's one and not three.

Both the father, his word and holy ghost are one so, don't confuse yourself with what you're been taught.

That's why modern writings are trying to correct that error by ommitting the trinity stuff.

Note that The word "trinity" had never appear in any bible translation

There are tons of other scriptures that support the Trinity.

Following!