I have 16 lenses and two systems (Nikon F and mFT), but for more than 90% of my shooting I only use one lens per system - and only one system (FF) for more than 85%.
Nikon FF with 150-600 and mFT with 12-60.
I have a Viltrox adapter that let me use my F lenses on mFT, with working AF. The Nikkor 70-200/4 works well on mFT, but doesn´t amount to many % of my shooting. That is a reasonably good lens that don´t find much use on it´s intended body either...
Maybe I should have had a plan before buying all these lenses