I was able to successfully import a QBO file after getting the error by following the below article. After trying different options, this one seemed to work.

Backup your old fixer.txt file from your resource folder. Copy the Quickbooks 2023 fixer.txt file from the link below. Replace your old fixer.txt from QBXXXX version with the QB 2023 version. Restart QB and it should work.

Once it starts working, DO NOT select check for updates or turn on automatic updates.

Mine was QB 2020 version, and I presume it should work for other unsupported versions as well.

Actually this article helped me solve the problem:

https://quickbooks.intuit.com/learn-support/en-us/help-article/bank-feeds/error-ol-222-downloading-w...

I downloaded the 2023 fidir.txt and replaced my old 2020 fidir.txt file with the 2023 version.