Interestingly, they seem to address this on their legal page[0].
Despite this, it does seem like just installing Windows and then attemting to debloat post-install is the least risky option than just trusting a third party Windows installer.
I used to like Blackbird for this, but after breaking updates and the Store enough times I’ve learned my lesson. O&O ShutUp10++ is all I used to debloat now, in addition to MassGrave activation. NTLite is the nuclear option if you’re prepared to invest a few hours crafting your “perfect” image.