I fried the battery charging chip for my HTC dream when I rooted and used it as a router for the family in holiday. I felt it was hot to the touch but I thought "it's gonna be ok, surely it has temperature sensors and it will throttle". High draw for a long time when charging = the chip exploded and it wouldn't charge anymore. Luckily the battery was removable and I already got an external charger for it from dealextreme. But HTC still repaired it for free under warranty even if it was my fault and I gave to them back rooted.
Same for LG when my rooted Nexus 5X boot looped, although that was an endemic problem caused by LG shitty manufacturing (they changed the stance a few months after that, never bought LG anymore)
Samsung should repair it, I thought they were the only ones root friendly left on the market...
wdym literally all phones can be unlocked without a waiting period, account, internet connection or any other bs (it trips the knox e-fuse tho)
you just go to the settings, enable oem unlock and run fastboot unlock.
it's as straight forward as it gets and works on all devices that aren't locked to a carrier or sth (which is mostly an us-exclusive issue)
i was using my older mi play as a router (temporary solution) until we moved and got a proper internet connection. (we were very close to the poland-ukraine border back then and only my old phone was able to pick up vodafone ua's 4g signal across the border)
it shut itself down multiple times and was constantly turning off the tethering mode due to overheating.
it still has vibrant permanent yellow burn marks on the display around the hot spots and only drains 0.5a while charging no matter what.