My investment account balance is low compared to my lifetime future earnings - even at 100% stocks, I'm arguably under-exposed to equity bull markets.

I don't follow the logic. What does your future lifetime earnings have to do with the returns of the market?

Sounds like the fascinating but terrifying 'mortgage your retirement' theory: https://www.bogleheads.org/forum/viewtopic.php?t=5934

Thanks for that! I have no idea what's the lesson to take away, but it sure was an interesting read.

If a bundle of stocks worth $1MM at retirement is worth $100k today, then in order to save up $1MM at retirement I need to earn $100k more than I spend. If the stock market goes up 20%, then I now need to earn $120k more than I spend, putting retirement further away. Call options protect against this, giving relatively cheap insurance against huge market upswings.