The DisableAsyncExports workaround does not appear to work in InDesign 2025, but continues to work in InDesign 2024.

The .jsx scripting option to disable background exports that was initially documented in this article stopped working a few versions ago as well. https://creativepro.com/a-new-workaround-for-that-pesky-background-export-issue/.

That article was from 2011. That's how long users have been working around this problem, Adobe. The background export is seriously flawed when it comes to large files with a lot of links. The foreground export works just fine with the SAME file, so it's not our files--it's the background export process.

Please fix this!!

In rare cases, PDF files exported from InDesign have defects such as missing images (alerts are not displayed). The cause is thought to be PDF output in the background. Therefore, users add “DisableAsyncExports.txt” to avoid PDF file failure. This is a very cumbersome operation. Users have been waiting for years to be easily turned off in the background task panel.

Japanese:
InDesignから書き出されたPDFファイルは、まれに画像が欠ける等の不良が発生します（アラートは表示されません）。その原因はバックグラウンドでのPDF書き出しであると考えられています。そのためユーザーはPDFファイル不良発生を回避するために「DisableAsyncExports.txt」を追加します。これはとても面倒な操作です。ユーザーはバックグラウンドタスクパネルで容易にOFFにできることを長年の間待ち続けています。

The https://www.publishingblog.ch writes about it:
There is a very simple way in InDesign to bring these file exports back to the foreground. Create an empty text file - with a text editor and not with a word processor! - and calls it "DisableAsyncExports.txt". Copy this file into the InDesign program directory.
But I haven't tried it out to see if it works.