Poor rating

[seastar]

I just finished a phone conversation with my insurance carrier.
I called them to renew my policy and to inquire about adding my 24 year old grandson to the insurance coverage on my CC-160.
He has 500 + hours and is a flight instructor in a part 141 flight school, flying and teaching daily.
He has commercial, instrument flight-instructor and tail wheel ratings.
my insurance carrier told me they are no longer insuring Carbon Cubs for pilots with less than 100 hours time in type.
when I asked why, I was told it was because of the "very large number of loss of control on landing accidents".
They said the airplane was "so light" that there were lots of damage accidents.
Have any of you had similar reactions from your insurance carrier?
Bill