Samsung phones probably just about warrant their current prices. Best screens in the industry, always well made, waterproof, headphone jack, sd card slot, arguably one of the best cameras on Android and Samsung Experience has actually transformed into something that adds a lot to Google's barebones featureless AOSP.
When you start going super cheap with Xiaomi you tend to lack NFC, have to play the screen quality lottery with cheap LCD panels and even with phones being sold in Europe warranty is always a concern with less established manufacturers. Or no warranty if you're importing from China.
I don't think you can say Samsung overcharge as such, just there is competition if people are willing for some corners to be cut. Apple definitely overcharge, but you're paying for the brand/paying into a closed ecosystem with zero hardware competition.
The OnePlus was becoming a good competitor for Samsung, but lol at them cutting the headphone jack. They're starting to do what most companies do when you grow your brand, ramp up the price and follow the trends set by Apple/other bigger manufacturers.