Calculated Measure percent not blank

You need to upgrade to the March 2021 version of Power BI Desktop. It supports multiple columns now.

If you cannot, use this measure:

CALCULATE(
    COUNTROWS( 'Table' ),
    FILTER(
        ALL(
            'Table'[MVA?],
            'Table'[Insurance 1],
            'Table'[Insurance 2]
        ),
        'Table'[MVA?]
            = TRUE()
            && ( 'Table'[Insurance 1] )
                <> BLANK()
            || 'Table'[Insurance 2]
                <> BLANK()
    )
)

But you should be on March 2021 if possible. Only do the above if your IT overlords are evil, or you are on Report Server, which will get this feature in May I think. 😁