NGnius

All browsers on iOS are basically reskinned versions of Safari since they all have to use WebKit

Looks like the back (and side) cover clips on. IFixit has repair guides available already. Inside, it looks like basically any regular phone. No Fairphone-esque modules. The inside seems to be well-designed for repairability though -- separate bottom board and battery pull tabs. All of the side buttons are attached to the back cover and a thin cable connects to the main board under some plastic. That's going to be easy to break while repairing...

I looked at all 3 phones, they are all similarly built to the Pro model I linked.

Chromium is still controlled by Google, so having an overwhelming market share of Chromium-based browsers reduces competition and increases Google's control of the market's position and future. Using Firefox (and Safari, if it were not locked to a single ecosystem) reduces that threat.

It being harder to repair means it shouldn't be repairable? That's an... interesting stance to take. Right to Repair is all about giving people the information and resources necessary to make a repair, especially if it's not designed to be repaired.