No they don't. The text is very clearly conveying what this project is about. Not everyone needs to cater to weirdos who are obsessed with policing how other people use LLM.
The people who don't care about LLM slop being shoved down their throat at every turn are the "weirdos" here. The project might not be slop, but the website certainly is, and it's perfectly reasonable for people to stop reading immediately and decide that they don't care about what could be an otherwise useful project when they determine that the author didn't give enough of a shit to even write the text on the website themselves.
But there is an old-school README.me at the github homepage: https://github.com/stanford-scs/jai
The repository has an old-school ASCII INSTALL file.
If you don't like the vitepress site, just use github and read the human-written README and man page there. All the information you need to use the software is available without laying eyes on any AI slop. Of cource, if you hate AI so much that you can't get past a vibe-coded landing page, you might not be the target audience for jai, because you probably aren't doing a lot of vibe coding. But maybe jai is still useful to you for grading programming assignments or running installer scripts.