I need a tool to see the entire post history of someone
I need a tool that can show me stuff even after they have edited it
You have it all with the forum, go to that user's post history. Click on their username, click on "Show the last posts of this person." and you will get what you want, only current version of their posts. If they edited their posts, you will have only their edited posts. For original posts, go to scrapers and their archives like Ninjastic.space or Loyce.club but they have limitations, said above.
There are people here whose post history I definitely need to go through before jumping into bitcoin
Who is a forum poster you need to read all post history before jumping into Bitcoin?
Is the user Satoshi Nakamoto?
satoshi accountsatoshi account's post historyThe complete Satoshi from Satoshi Nakamoto Institute, a third party site, not from Satoshi Nakamoto with archives of Satoshi's posts, emails, more.