That isn't how it happened. There is an Isaiah Scroll manuscript that dates to before Jesus time. So NONE of the prophesies about Jesus that were in the book of Isaiah could have been altered after Jesus came. And there are many, many, verses describing Him in the book of Isaiah.
How do you know about other manuscripts which didn't make the grade because it appeared they had errors? You see, after the fact it is easy to cherry pick what goes into the bible and cherry pick what doesn't go in. Called selective bias. Then call it the word of God because it seems so perfect.
In a 1000 years time if we are still around, The Book of Revelations will look nothing like todays version. They will have added bits and removed bits, using the excuse, 'interpretation'.
That's not true. There are lots of Isaiah manuscripts, some only are partial, but aside from some scribal errors, they are very close to what we have in the Bible. There is one copy of Isaiah that has been proven to have existed before Jesus came. Go ahead, try to find an Isaiah manuscript that doesn't match up with the Bible. I haven't done the research, but I'm assuming that there aren't any. So are you saying that before Jesus came, there were erroneous copies of Isaiah that didn't meet the grade, so they were discarded, people only kept the Isaiah copies that contained the prophecies of Jesus? That is ridiculous, but maybe that is what you are trying to say.
Don't put anything past human beings, we are corrupt to the eyeballs, seriously! And you guys think the church is lilly white....??? LOL
https://en.wikipedia.org/wiki/Isaiah_Scroll The exact authors of 1QIsaa are unknown, as is the exact date of writing. Pieces of the scroll have been dated using both radiocarbon dating and palaeographic/scribal dating. These methods resulted in calibrated date ranges between 356 and 103 BCE and 150–100 BCE respectively.
Think a bit. The book of Isaiah may be complete, maybe, but there could be errors in interpretation. Saying that, there may be further manuscripts from the same author or the same body where Isaiah came from that were not included. They may have not been included as they contained information that did not meet standard/did not meet the narrative/contradicted/had a differing opinion to the prevailing thought of those compiling the bible at that time. A bit like a failed trade "oh we won't add this bit".
Now its been years since I was into bible study, but I recall reading somewhere there are manuscripts removed from earlier versions of the bible.
So you will dismiss the evidence simply because there might be another explanation, that we have no evidence for?