It makes more sense when you know that 2nd temple Judaism had an entire economy built around animal sacrifice for sins, and that the temple central to that is destroyed a few decades after Jesus died as Christianity was starting to take off.

So positioning Jesus's death not as an embarrassing failure to manifest earlier messianic prophecy but as this ultimate sacrifice making the animal sacrifices that could no longer be performed unnecessary was a very convenient belief to attract Jewish converts.

Of course, then Mark 11:16, where Jesus bans anyone from carrying animal sacrifices through the temple in the first place while alive becomes an inconvenient detail, which is probably why it later disappears from Luke and Matthew.

So Christianity probably really was a split from 2nd temple Judaism at the time of Jesus on the point of animal sacrifice, but then following his death the death itself gets reworked back into the paradigm of animal sacrifice by those coming later (i.e. Paul) which then later makes it more attractive to Jews who no longer have a temple after 70 CE when it takes even greater prominence.

The irony of course is that looking at some of the early apocryphal sayings of Jesus on the ridiculousness of sin and salvation as an inherent birthright that shouldn't be given over to another to be lent back out at interest - this development of the crucifixion as an ultimate sacrifice on behalf of humanity was possibly the exact opposite of a historical Jesus's whole point, even if it was favored for survivorship bias given the destruction of the temple.