Git is currently industry standard tool for software development, which means that almost every IDE and code editor has good and mature GIT integration. It will take a while for Lore to achieve similar level of support. Considering the intended usecase seems likely that they focus the effort on integrating into game engines and game development specific needs instead of making plugin for every last code editor. Not only code editor but every other software related tool interacts with version control - code review tools, CI, package managers and code forges. That's a lot more work than just creating a version control system. Why waste effort on areas that already have good alternatives.

Code forges lead to the next reason -> they are making it open source (see the faq for why). If they want community collaboration it makes sense to prefer industry standard tooling. Organization internal consistency doesn't matter to external collaborators. Various Google projects with all their custom tooling are good example of what happens if this gets ignored. Every time I have to deal with depot_tools or repo it's a pain.

Third reason not to self host is that it's not quite production ready (see "Is lore production-ready?" in the FAQ). Can't be self hosting from day 0 and once you have a working setup you need better argument for switching just because you can. If lore was attempting to make a statement that it's a superior method of version control for regular source code it would be a different story.