Considering how many marriages end due to finances and how often couples fight over money, "wastes money" is probably one of the least desirable traits in a future spouse.

"Failure to see reason" is probably the next biggest red-flag/dealbreaker for me.

I'm going to die alone.

Fortunately it's the future. Just (gently) advertise on your Tinder (well, more likely Hinge) profile that you've watched that movie about blood diamonds and will be buying your and your future wife a lavish foreign honeymoon instead of a blood diamond to pre-screen potential dates if it's a deal breaker to you.

Yeah well that’s society for ya. If you go with lab grown make sure you only go for a size that’s actually achievable in natural-diamond prices for your income level. The signaling game (silly as it is) is good at outing “that’s an excessively large diamond for his/her income, must be lab-grown” versus “that’s a large diamond for his/her income, that’s an indicator of priority.”