Yes, I use the WP Discourse Comment Block on another site where we have a FSE theme so it is in the template.
My issue is that my blog’s Garfunkel theme does not support it, and the comments space is built into the template. I am not full on with a block theme development- can I insert a block via PHP in the template? I am looking at things like Testing and Feedback for using block based template parts in classic themes – Make WordPress Themes but am not quite sure how to integrate an existing block.
The only other way I could see is adding the WP Discourse Comment Block at the bottom of every post, but I have 88 posts in the site already.