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Samsung phones can survive twice as many charges as Pixel and iPhone, according to EU data
(www.androidauthority.com)
This is a most excellent place for technology news and articles.
(Not saying this was your case, but generally good to check) - a finicky/wobbly USB type c connector has been a symptom of a dirty charging port several times in the past. Awful lint/dirt would get packed down into it, preventing the charger from fully inserting.
I ended up carefully and gently picking it out, though there are some delicate small contacts in there!
Anyway, good luck trying GrapheneOS! It's been my daily driver for months and past the learning experience it's great!