All you've said there is that you, personally, would not buy Nissan based on an unrelated statement that they tried to advertise their batteries lasting a long time.
Unless you have worked for Nissan with inside knowledge, you are not qualified to make the bold statement.
Keep digging that hole of yours
I think what
@broc was trying to get at, is that there are many things that could write-off a car, as I'm sure you know full well. There could be as simple fault as multiple intermediate signal problems to a few of the critical sensors (ABS/throttle body/steering/etc) and the cost to diagnose and replace the wiring loom could write off an old car.
My dad's Volvo, had intermediate problem with windscreen washer jet. We took it apart and couldn't find any problem, using multimeter and oscilloscope in combination with the car mechanic's wire pokey thing and wiring diagram in Haynes. Put it all back and it worked fine for a few days. Luckily a few months now, it appears to be working okay, but low washer warning has gone on holiday.