MAPT and behavioral variant of frontotemporal dementia: FTD phenotypes arise from different underlying proteinopathies (Chare et al., 2014; Josephs et al., 2011; Snowden et al., 2007); ALS‐FTD is primarily linked to pTDP‐43 (Geser et al., 2011), svPPA is nearly always associated with underlying TDP‐43‐C pathological aggregates (Bocchetta et al., 2020), nfvPPA is commonly associated with 4R tau (Spinelli et al., 2017) and molecular findings in bvFTD are thought to be heterogeneous (Perry et al., 2017).