I don't understand the claimed causal relationship.
FWIW, I'm paying rent for my current apartment, we don't have a gas supply, and I've never had a power cut.
Indeed, while I am rich and do own an apartment back in the UK, roughly three quarters of the 16.5 years since I've last experienced a power cut was in property I pay rent for, and only about 4 years were in the flat I own and began collecting rent on when I left the country. Which, ah, also doesn't have a gas supply.
In any case, not sure what this is suppressed to have to do with reliably of the electricity supply — it's not like landlords get free shares in local power grid companies (or if we do, I missed the memo).
Sorry but this is nonsense. Your local power utility monopoly is what it is, completely unrelated to whether you rent or own.