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Why Charging Your Gadgets Over 80% Is Such a Bad Idea | iFixit News
(www.ifixit.com)
This is a most excellent place for technology news and articles.
The biggest barrier for "most people with moderate skill" is having to acquire equipment to replace the battery. Once it becomes too much effort and cost it's better for most consumers to take it to the manufacturer or 3rd party service for replacement.
I stopped replacing batteries once I needed to heat the adhesive to remove the back and screen as I don't have that equipment to hand, and initial attempts caused damage to the screen and back cover.