Have you tried the test site referenced topic #49627 ?
git clone --single-branch -b hugo-forum-topic-49627 https://github.com/jmooring/hugo-testing hugo-forum-topic-49627
cd hugo-forum-topic-49627
hugo server
That is still the best approach, and the configuration is necessary, otherwise I would not have included it.
And for the record, this is still a really stupid Obsidian bug/limitation:
https://forum.obsidian.md/t/start-absolute-path-with-a-leading-slash/32501