Deactivation destroys what could otherwise be something very collectible, same old reason for me deacts sell more readily than original revolvers.
Or it could be that they are classic family pieces that the only way to keep them is deactivation if that’s the reason go for it, definitely not cheap to achieve but it keeps them in the family.
Personally (whatever the age) l would sell them on to someone with the relevant certificate but that’s only my opinion, l had until recently six revolver’s that l collected over the years and were very collectible so rather than deactivate them l sold them on again just my personal preference.
Its definitely your personal choice.