The UI lookr great, but I have the same question. What is the workflow / use case for this?
Some people just need to glance at their schedule to make a decision or plan.
Overall these type of cmd line tools like taskwarrior are for folks who want one thing at that time and wish to take the shortest, least cognitive overhead path to getting that thing/info. Same reason I use tz instead of browsing to a site with Timezone calculators. Same reason I use vifm to find and edit files.
Some people like to use devices buried in bling. Some people don't.
The tool seems a great idea (I was equally shocked that it's all Bash scripts, and expected Rust), but calling it -- with bash ./dline -a on MacOS X -- I get plenty of syntax errors.
Is that the ancient system version of bash? I'd try with a current version and see if that works.