The goal is to ship games. Games have a fuzzy definition and what you're building always changes during the process. Iteration is very important. You can that by noticing that every game engine has a non-compiled scripting tier usually on top of a slow to compile core.

DoD lets you tweak data w/o a recompile. Data is composable and transferable. DoD is highly iterative and that's a major reason why its in the running.

That said, its also nice that DoD can fairly easily be array oriented and that's where a lot of the speed comes from.

As far as DOTS goes, Unity has been advertising the performance pretty hard because in the short term its going to be a step down ergonomically.