It’s apples and oranges, really.
Shadowdark is an OSR game with underlying mechanics very similar to 5E but with changes to push things in a decidedly old-school direction. Anyone who’s run any OSR game or old-school D&D could run a passable Shadowdark game with a read of the book and whatever prep time they normally take for such a game. The quick character creation and high lethality make it great for one-shots and convention play. And there are about 50+ years worth of content you can mostly directly draw from. So it’s very easy to pick up and play.
Daggerheart is a Frankenstein of new and old that everyone will need time to adjust and learn to run it well. Even people who ran it during the open beta are having some trouble adjusting to the final release. To run Daggerheart well you need to either come from a PbtA or BitD background already or learn that style of play. That learning curve can be huge for people only used to D&D. Besides that, the game is focused on long-term OC play with the PCs as the protagonists. Character creation is slow and involved the entire group. This makes it especially bad for one-shots and convention play.
It’s like judging a monkey and a goldfish based on which is better at climbing a tree.