As creators, we have two choices: We can laugh at the "dumb query," or we can realize that
And if you are one of the thousands of people who typed that query today? You are not bad at computers. The computers are bad at you. Here is your solution: Use gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/ebook -dNOPAUSE -dQUIET -dBATCH -sOutputFile=output.pdf input.pdf (Ghostscript). Now go back to work. Have you ever been blocked by an 8MB limit? Share your war story in the comments. Or just download a blank 8MB test PDF and move on with your life.
The user does not want to fix their file. They want to replace it. They have given up on remediation. They believe that somewhere on the internet, a perfect, pre-optimized, 8MB PDF already exists for their purpose.