I thought I read somewhere that ads make a blog seem more authoritative so I disagree about not having ads.
1. "Measuring Consumer Sensitivity to Audio Advertising: A Field Experiment on Pandora Internet Radio", Huang et al 2018: https://davidreiley.com/papers/PandoraListenerDemandCurve.pd... [experimental]
2."The Effect of Ad Blocking on [Firefox] User Engagement with the Web", Miroglio et al 2018: https://research.mozilla.org/files/2018/04/The-Effect-of-Ad-... [quasi]
3. and my own A/B test: https://www.gwern.net/Ads [experimental]
Way back when I experimented with ads and links but I came to the conclusion that the money was pretty trivial in the scheme of things and it took away from the otherwise non-commercial nature of my site.