Wealth and ability to seek help are mutually exclusive. For sure, you have access. But you have to want it, even if some are desperate to help you and others are desperate to extract from you while you remain in poor health. Maybe someone could’ve advocated for a conservatorship, but we’ll never know why someone didn’t.

(have had friends and loved ones addicted to alcohol, cocaine, heroin, etc)

I don't think these things are exclusive to each other. Someone who is struggling mentally can be very successful in their career and can have a sea of people ready to reap the rewards of their success. That kind of behavior can absolutely manifest in the person spiraling or spiraling further.