[j15t]

Just to be clear, most insurance companies have very strict risk management policies and almost exclusively invest capital in government bonds. As you are probably aware, these bonds have had very low rates of return in recent years - getting close to 0℅ yield (or even negative yield in some regions)

So I don't think the difference in efficiency will always be a significant factor.

In addition it is possible to create bond tokens on Ethereum, which might provide opportunities to invest the capital from premiums - provided that the bonds have sufficiently low risk.