The more universal solution would be to standardize Reader Mode compatibility, and for browsers to let users configure how they want Reader Mode to look.

In other words, instead of an n x m solution where every web site has to cater to each different user preference, there should be a simplified content view that every web site only has to support in a singular way, and that allows browsers to cater to the various user preferences.

for OLEDs, I tend to prefer pure black because it doesn't burn-in. Since they have a limited lifetime, any "on" time is costing me usage in the long-long-long run and I'd rather have my monitor last 5+ years than ... 2 or 3.