We just started using these at my job. I like how the approach takes the conversation out of a slack thread and generates some documentation to boot. The tooling ecosystem is also excellent (adr-tools is awesome) and you can easily integrate stuff like confluence document generation as part of your ci pipeline.
We've taken the approach of submitting adrs as a pull request on the repo they affect (we have a dedicated repo for higher level adrs) and submit the link to a dedicated slack channel so folks can have a look and submit any comments they might have on the proposed decision. Once everything has been hashed out, we either merge the PR and get busy implementing the idea or close out the PR and move on.