I think similarly to the above, BMW know their machines (both cars and bikes) are not 'competitive' in the same way - they are focused luxury brands, and in the case of the motorcycles, querky designs - and are sold to general mass market customers, not specialist niches?
BMW is a multi billion dollar company, and by extending their racing arm to associated brands, it minimises and disassociates any 'bad press' should those teams not do particularly well, in what is a very competitive but still niche field... noone in Munich wants to see a headline "BMW fail in.... [whatever]" in the press?
Ehm, what BMW enduro bike should be the kit based on please? G450X is finished and as far, as I know, there is no other bike on the way. Not to mention, that investment in speedbrain kit development for Husqvarna is quite OK...